► BMW M5 vs Audi RS6 and Porsche Taycan
► PHEV M5 vs combustion Audi and electric Porsche
► Is the BMW the perfect blend, or the odd one out?
The new BMW M5 is a plug-in hybrid. The perfect blend of petrol (Audi RS6) and electric (Porsche Taycan), then?
Pre-flight briefing: BMW M5
What’s the line-up?
Plug-in hybrid V8 gives seventh-gen M5 bandwidth like never before, whether you want to drive emissions-free or smoke up 717bhp through its rear tyres. Cheapest-on-test at… £111,405.
Data
Price £111,405 (£133,670 as tested)
Powertrain 18.6kWh battery, 4395cc 32v twin-turbo V8, eight-speed auto, all-wheel drive
Performance 717bhp @ 5600rpm, 738Ib ft @ 1800rpm, 3.5sec 0-62mph, 191mph
Weight 2435kg
Efficiency 148.7-176.6mpg (claimed), 13.5mpg (tested), 1963-2331-mile range (claimed), 178 miles (tested), 37-39g/km CO2
Length/width/height 5096/1970/1510mm
Boot capacity 466 litres
Read our BMW M5 review
Pre-flight briefing: Audi RS6
What’s the line-up?
The, erm, lightest car on test – twin-turbo V8, eight-speed auto and all-wheel drive. In ‘Performance’ guise, it means more power and a new centre diff. Carbon Vorsprung spec throws in every option.
Data
Price £133,520 (£133,520 as tested)
Powertrain 3996cc 32v twin-turbo V8, eight-speed auto, all-wheel drive
Performance 621bhp @ 6000rpm, 627Ib ft @ 2300rpm, 3.4sec 0-62mph, 174mph (limited)
Weight 2100kg Efficiency 22.4mpg (claimed), 12.5mpg (tested), 360-mile range (claimed), 201 miles (tested), 286g/km CO2
Length/width/height 4995/1951/1460mm
Boot capacity 565 litres
Read our Audi RS6 Performance review
Pre-flight briefing: Porsche Taycan
What’s the line-up?
Porsche’s electric icon is freshly updated with more power and faster acceleration, plus it boasts swifter charge times and an increased range. Here in Turbo guise, it makes 872bhp and costs £134,100.
Data
Price £134,100 (£167,485 as tested)
Powertrain 97kWh battery, twin e-motors, two-speed gearbox, all-wheel drive
Performance 697bhp (872bhp with launch control), 657Ib ft, 2.7sec 0-62mph, 162mph
Weight 2290kg Efficiency 3.5 miles per kWh (claimed), 1.9 miles per kWh (tested), 394-mile range (claimed), 184 miles (tested), 0g/km CO2
Length/width/height 4962/1966/1381mm
Boot capacity 366 litres (plus 84-litre frunk)
Read our Porsche Taycan facelift review
M5 vs RS6 vs Taycan: the test
Flying west at a very healthy lick, despite the absence of light or dry tarmac, BMW’s new plug-in hybrid M5 is dispatching pre-dawn miles like a pebble skimmed perfectly over a tarn. It compresses rhythmically on its suspension and takes giant strides each time I dip into its 717bhp performance. Slip roads and bridges strobe past as tiny touchpoints on the surface.
The M5’s astonishing velocity proves so accessible and its chassis so stoic that, were the M50 a derestricted autobahn, I’d probably settle at 150mph as if it were a gentle canter. As it is I have to exercise serious self-restraint simply to avoid appearing on the news, let alone in the local magistrates’ court.
This much you’d expect of a super saloon that’s more powerful than any of its predecessors. But it’s when I leave the boring roads and head for the valleys that the M5 truly starts to get under my skin.
The road wraps around the contours of the landscape, clinging to mountainsides as the surface ripples over subsidence and snakes between imposing rocks and walls. That endless slug of power continues to define the M5, but there’s a dexterity here at odds with a body as long as a last-gen 7-series, not to mention somewhat chunkier.
M xDrive easily deals with the surplus of power. There’s total composure with a strong bias to the rear in its standard setting, but slackening stability control to ‘unlock’ 4WD Sport mode is like exploring a powerful rear-driven car’s outer limits with an unintrusive safety net. No doubt the track being some 75mm wider at the front and 48mm at the rear compared to a regular 5-series helps.
I roll speed into corners like I’m sending a bowling ball at 10 pins, and when I get back on the throttle at the apex the rear tyres chew at the surface and the M5 yaws just a fraction while gathering speed at a furious rate. Its footprint means the M5 can’t disguise being a very large car, but never does it feel close to unravelling here.
It’s even nicely balanced in full rear-drive mode, though the M5 is now a long way beyond making that a sensible proposition for most driving (not least because M has opted to omit the variable traction control of other M cars).
Three hours after leaving home, I roll into a Welsh car park as hybrid mode kills the M5’s engine. There’s no one for miles and all I can hear when I lower the windows is the crunch of tyres on gravel and the lazy slice of wind-turbine blades cutting the air overhead. Everything that dares breaks the silence is amplified like ASMR on noise-cancelling headphones. Blimey. Is this the most rounded performance car I’ve ever driven? It just might be.
To get some context on that, I’m here to meet two rivals – the V8-powered Audi RS6 Performance and the all-electric Porsche Taycan Turbo, both of which enjoy recent-ish updates and represent the two opposing schools of thought M mulled in M5 development.
Neither will be able to stretch quite like the M5, but they might just do the most important bit in the middle better.
Starting from £116,120, the Audi comes in a little pricier than the £111,405 M5, produces 621bhp and officially returns 22.4mpg. The Taycan Turbo, meanwhile, costs £134,100, extends to – yes – 872bhp in its overboost mode and can now stretch for up to 376 miles between charges, according to WLTP figures.
Parked alongside the M5, the visual differences are stark. The BMW’s dramatic if polarising design echoes Chris Bangle’s E60 M5 in its avant-garde surfacing (maybe Doctor Who’s K-9 too with its pyramidal taper and largely featureless flanks?), where the Audi blends sophistication with muscularity and the Taycan is pebble-smooth and gorgeously low-slung; it does the 911-with-more-doors thing far better than any Panamera ever has.
Perhaps astonishingly, both rivals are significantly lighter than the 2435kg BMW, and both have superior power-to-weight ratios – if only by a solitary bhp in the case of the 296bhp-per-tonne Audi.
Partly we have uncertainty around electrification to thank for both the M5’s multi-tasking genius and a kerbweight more than 500kg chunkier than its hardly svelte predecessor, because when BMW’s M division began development of the G90 M5 five years ago, the outlook was so confused it decided to pack everything just in case. Increasingly this looks to have been a shrewd call.
In addition to the 4.4-litre twin-turbo V8 descended from the F10 two generations back, and the eight-speed auto and M xDrive all-wheel drive introduced with the F90 last time around, M has packaged an electric motor in the gearbox, plus a chunky lithium-ion battery with a usable capacity of 18.6kWh.
The latter accounts for around 220kg of the M5’s heft, is tucked either side of the transmission tunnel and required so much under-body bracing to bring it up to M standards that the team skipped Christmas holidays in 2022. (It’s also why you sit a fraction higher than before.)
The performance stats are astonishing. The V8 produces 577bhp and 553lb ft, the e-motor lends a further 194bhp of instant muscle for 717bhp and 738lb ft all in, yet it’s good for over 40 miles and can travel at up to 87mph on e-power alone (though not both at the same time).
Crucially, with the battery depleted, BMW still claims a max 27.7mpg – a figure that not only improves on its predecessor by 2mpg but smokes the Audi by 5mpg too.
It’s both a mighty engine and a beautifully integrated powertrain, stand-outs being the smoothness of its transitions between petrol and electric, a midrange that swells like a tidal surge and throttle response so instant it’s like the e-motor is permanently poised in its blocks, waiting for the starting pistol.
Its lovely warm burble is punctuated by percussive little explosions that rumble each time I back off. When I pull and hold the left paddleshift to drop as many gears as possible and activate Boost mode, the M5 takes off like a firework that’s toppled over. It’s phenomenal.
Never mind that power-to-weight actually falls compared with the previous M5 and that it’s a fraction more leisurely to 62mph at 3.5 seconds; the muscle and synaptic connection here represent awesome progress.
But if the M5 is extremely good, it is also imperfect. Complexity threatens to overwhelm the driving experience, with so many elements to configure – multiple modes for hybrid settings alone, far more to tweak dampers, steering, brake pedal feel etc – that even storing two preferences in M1 and M2 shortcut buttons feels clunky.
Perhaps more troublingly, the M5’s suspension tenses so dramatically over one particularly challenging section of moorland that its Comfort setting feels more like a Sport+. Hmm.
While James Dennison heads out to get us a second opinion, I swap into the RS6.
First impressions? The infotainment might be inferior to the BMW’s, but the Audi has the nicer cabin, one that looks strikingly uncluttered and clean after its chintzier rival. You sit down lower than in the M5, in supportive sports seats that have a little extra squish in their bases, and grip a slender steering-wheel rim wrapped in highly textured alcantara.
Simply running your hands over this wheel at a standstill makes the RS6 feel lighter and more agile than the M5’s leather-wrapped chubber, and that’s exactly how it translates to the road. It’s not exactly chatty, but there is more surface fizz than in the M5, making the newcomer feel aloof and isolated in comparison.
RS6 fundamentals remain unchanged, meaning a twin-turbocharged 4.0-litre V8 with a dash of mild-hybrid assistance plus an eight-speed torque-converter auto and all-wheel drive. But Audi has now replaced the base model with the RS6 Performance, bumping pricing by £15k while sweetening the deal with extras including the brilliant Bang & Olufsen 3D sound system and 22-inch alloys.
There’s also a new centre differential and a gentle 30bhp/37lb ft performance tickle for 621bhp with 627lb ft torque all in, while 8kg less of sound deadening lets a little extra V8 music through to the cabin – a lovely bassy bob-a-bob-bob that manages to be both richly cultured and goose-bump exciting when you get on it.
This TFSI might hit snooze until 2300rpm and can’t respond as crisply to the throttle as the M5, but it’s muscular in the midrange, fires down the road in great lunges and has the most authentic, engaging soundtrack on test.
‘The engine is utterly brilliant, especially now with the E63 AMG gone,’ notes JD. ‘It sounds like a hot rod, goes like a train, drinks ⊲ fuel when you’re on it and settles down when you’re not.’
Our car’s Carbon Vorsprung spec throws in virtually every extra save carbon-ceramic brakes and bumps pricing to £133,520. That’s a dead heat for our M5’s as-tested price thanks to the £19.5k Ultimate pack, which includes carbon-ceramic brakes.
Important to our Audi’s driving experience is Dynamic Ride Control with its coil springs and diagonally interlinked dampers that replace regular air springs, plus ‘forged-milled’ alloys some 20kg lighter than the stock 22s. Both are fitted to Vorsprung models as standard.
Any fears that the Audi’s upgraded suspension might be a compromise evaporate as soon as I head over the same moorland stretch that wrong-footed the M5. It is, to be fair, an unusually horrid surface, but the RS6 smooths over its corrugated ripples where the M5 jiggles, and generally allows its body a longer leash.
‘The RS6 deals with all types of road surface really well,’ notes JD later. ‘It also feels like the suspension has more room to breathe than the M5, which is far more rigidly locked down. Feels weird to say it in the context of an RS6, but it’s the more compact car by a margin.’
Ratchet its chassis up via the Balanced setting and the RS6 palpably tightens its muscles to the detriment of some comfort around town, but its underlying elasticity remains as speeds rise and simply feels more cohesive.
In fact, this car feels like it’s been sharpened on a whetstone after the near-identical Carbon Vorsprung I drove earlier this year, something most logically attributed to it wearing the Continental Sport Contact 7s as standard, not the Hankooks with which the previous press car was equipped. (That said, the M5 we’re driving wears Hankooks and feels fine.)
The Audi’s variable-rate steering and all-wheel steer feel more responsive than before, perhaps to the extent of being over-keen given I’m taking so many nibbles at the wheel to get through a corner. Nice agility, yes, but I’d calm it down a tad and perhaps use the M5 as a reference – it encourages more confident sweeps at the wheel despite having variable steering and all-wheel steer, too.
With the standard Sport differential left in its more relaxed settings there’s occasionally some front-end push on damp, quicker turns. But in its Dynamic setting the RS6 really hooks up – good turn-in, nice mid-corner body control with a hint of rotation and rear-biased traction that lets you flatten the throttle with only the tiniest chirrup from the rubber.
Remember when Audis had lead for shocks and understeered like a dog after a squirrel? Not this one.
I pull back in and swap notes with James, who’s grinning after his first miles in the M5. ‘It’s so confidence-inspiring and the steering and front end make it feel surprisingly delicate,’ he enthuses. ‘Variable-ratio steering and rear-wheel steering no doubt contribute, but I really like how you can move the M5 around just using your wrists. It hook ups so well if you want and with the electric motor you can fire it off from the corner like a rocket. Only the sense of width makes it feel so incredibly large.’
And the RS6? ‘Handles better than any RS6 I can remember,’ he concurs. ‘The steering is too light just off centre for my liking, so you don’t have that feeling of instant connection you do in the BMW. The rear-wheel steering is aggressive, but it didn’t bother me.’
Doubtless a significant number of you are looking at the M5 and RS6 and thinking ‘like that, but without the benefit-in-kind bill’, in which case the excellent Porsche Taycan remains the default choice for good reason.
Refreshed earlier in 2024, key updates across the board include extra power and acceleration, a 12kWh larger battery for additional range (always the Taycan’s undoing) and faster charging at up to 320kW – a 50kW increase. There’s also a handy charging planner integrated with the infotainment that prioritises faster chargers with 150kW-plus.
Our Turbo spec sees power rise by 81bhp, with its maximum 872bhp available for 10-second bursts (basically all the time, then…), while claimed range stretches a highly useful 78 miles to 394 miles. As before, there are two e-motors, all-wheel drive and a two-speed transmission on the rear.
A base price of £134,100 matches the ‘as-optioned’ price of the others, but extras push the Porsche to £167,415, with rear-axle steering (£1593) and Active Ride Control (£6291) most relevant to how this car drives – the latter upgrade combines air suspension with motor-controlled trick dampers to proactively dial out pitch and roll.
You sit down low in a perfect driving position on comfortable, supportive seats, with the Taycan’s low scuttle affording an excellent view forwards and a small-diameter steering wheel immediately teeing up a sporting drive. The little drive-mode controller that floats like a satellite below the right-hand spoke makes tweaking settings easier than in either the Audi or BMW.
James thinks the Taycan feels heaviest of the three at an amble, but fundamentally the handling is superb as I glide and swoop through sequences of corners like I’m on a toboggan run.
The steering has a cool, clean precision that lets you place it perfectly, the chassis shrugs off tricky secondary imperfections that fluster the M5 and you absolutely feel how little weight resides over the front axle and how much of the stuff is low down between the axles – you’d probably need a centrifuge to pull more g.
Rear-wheel steer is so natural I notice only the overall agility rather than an odd pivoting sensation, while Active Ride Control feels superbly integrated too.
It leans into corners in its more sporting modes and keeps the body flat during acceleration and braking, and while that could so easily feel like a simulator, the reality is entirely seamless.
Driven in almost all scenarios, the Taycan’s chassis feels impeccably resolved. Its undoing proves to be a sequence of primary undulations where the road bucks over subsidence – the Taycan just about parries the first hit, but immediately feels wayward as it rebounds and then fully bottoms out, smashing into its rear bump stops. To be clear, this is a pretty extreme section that also challenges the others, but only the Taycan runs out of answers.
‘The handling is great right up to the limit, at which point the mask well and truly slips and the Taycan feels its weight,’ agrees James. ‘The RS6 and especially the M5 are much better at keeping things together near the limit.’
We all reserve another black mark for the brake pedal, which is so vague that at one alarming point Piers Ward thought he’d pressed the accelerator and was about to travel as the crow flies. Everyone finds the softness unnerving.
This is a shame, because the Taycan is more rewarding to drive when its chassis does more heavy lifting, and having a dependable brake pedal is key to that. When I rely more on the e-motors to carry speed through twistier sections, I’m always aware how much energy there is under my right foot.
As a result I tend to corner using a fraction of the throttle, which means a layer of interaction is absent – that feeling of digging into the power you get with the petrol cars, of adjusting their potential by short-shifting gears to get the power down, feeling the urge build, the friction at the surface.
Instead this is a binary sensation of cornering on a breath of throttle then pushing it to the floor and essentially becoming a passenger for a few seconds, a kind of giddy thrill-ride sensation. For me, the novelty quickly wears off.
We all admire the Taycan and enjoy driving it, but it does leave it looking a little shaky as we reconvene to discuss our podium…
M5 vs RS6 vs Taycan: the final reckoning
Pitching a Taycan Turbo against petrol-engined icons was always a stress test, but it comes away with its head held high. It looks superb, feels beautifully built and drives with a fleet-footedness shot through with true Porsche finesse, while improved efficiency, a larger battery and faster charging greatly reduce the Taycan’s biggest weakness.
It is not, however, entirely convincing. An output of 872bhp is crushing but leaves us craving more depth, as impeccable handling ultimately runs out of answers in more extreme circumstances.
That’s all pretty inconsequential in the context of saving thousands on a company-car scheme – but on a level playing field, the Taycan places third.
Given we’re judging these rivals against performance criteria, it’d be perverse to put one that wasn’t as engaging to drive ahead of another that ultimately out-performed it. Which is why the Audi is second.
Its exterior design is arguably more pleasing, its cabin calmer and more elegant. Its V8 engine is also more characterful than the M5’s, plus it’s hundreds of kilos lighter, feels more compact on the road and offers more delicate steering.
Shod with Contis and optioned on Dynamic Ride Control suspension, the RS6 handles with sure-footed dynamism and strikes a better balance of chassis control and compliance.
But the M5 takes performance to another level. Adding electrification to M’s V8 only intensifies the experience, endowing the M5 with the kind of high-rpm ferocity that makes the Taycan feel one-dimensional and even the RS6 a little short of breath.
Its chassis matches the RS6’s all-weather security but adds more poise, even in its more conservative setting, and far more adjustable handling in 4WD Sport and RWD modes. Variable-ratio steering and all-wheel steer are also more seamlessly integrated than the Audi’s similar hardware, snapping up the M5’s responses without ever feeling over-egged.
Our lead-footed testing averaged only 13.5mpg but that’s to overlook the 30-plus miles of e-power in reserve, all harvested on the go. With routine charging, the potential for huge efficiency gains is self-evident.
Few cars stretch like that. M5 for the win.
M5 vs RS6 vs Taycan: the verdict
First place
BMW M5
Too big and too heavy but marries epic performance and incredible handling
★★★★
Second place
Audi RS6
A fabulous daily driver that bristles with V8 character and knows how to entertain
★★★★
Third place
Porsche Taycan Turbo
Improved efficiency and agile handling but Taycan ultimately lacks rivals’ engagement
★★★★
