BMW M5 vs Audi RS7: Super Saloon Showdown

Hybrid power meets the super saloon

The arrival of hybrid power has been obvious for some time. I do not mean the canary-yellow, hippopotamus-sized BMW M5, whose subtlety as a Q-car is roughly comparable with Elon Musk’s contribution to international relations. I mean hybridisation itself. It now appears everywhere, from crossovers to supercars, with electric assistance improving both output and efficiency. Yet in the class where it seemingly makes the most sense, the super saloon, it has attracted an unprecedented amount of controversy.

A plug-in hybrid system ought to suit a super saloon perfectly. These cars are not supercars, so there is room to accommodate the necessary hardware. It provides an answer to anyone criticising your thirsty V8, while also delivering enormous figures to discuss with fellow enthusiasts. It adds another dimension, fills turbo lag to sharpen response and reduces fuel bills. Weight is the only obvious downside, but how much does that really matter in the booming super saloon category?

BMW’s answer must have been ‘no one’, because it cheerfully launched an M5 more than half a tonne heavier than the model it replaces, then watched the backlash build. Mercedes had experienced much the same response after revealing that the C63 would say farewell to its celebrated V8 and welcome a 2.0-litre four-cylinder engine supplemented by an electric motor.

Photography: Jonny Fleetwood

As we established some time ago, Mercedes has not got the C63 right: it was beaten by an Alfa Giulia QV that feels as ancient as Italy itself. Whether BMW ever intended to reduce the M5’s engine capacity is unknown, although it must surely have appeared on an early planning board. Retaining the V8 and boosting it electrically through a 194bhp motor packed into the gearbox gives the BMW M5 a set of figures without precedent. It enjoys more than 100bhp and 100lb ft over its opponent here.

That opponent is the Audi RS7. It uses petrol power alone, and therefore avoids the mass of a 22kWh battery, power inverters, motors, wiring and all the other equipment responsible for adding half a tonne. On its 22-inch matt-grey wheels, the RS7 is a brilliantly handsome machine. Audi understands posture and presence in a way BMW does not.

Across four decades, though, this is the first M5 to receive fresh exterior body panels. Every preceding M5 made do with revised bumpers and side skirts, whereas this generation gets new metal in the form of enlarged wings and wheel arches. Those swollen panels cover front tracks that are 75mm wider than on the standard 5-Series. Had you noticed?

It still feels like a squandered opportunity. The BMW does not crouch over the road remotely like the RS7. The Audi is all broad shoulders and confidence; the BMW looks awkward through its flanks and front end. This is not among the finest-looking M5s, appearing rather heavy-handed instead. Naturally, that makes it the better Q-car, as few people would suspect what lies beneath. Unless, of course, it is finished in Speed Yellow.

BMW M5 and Audi RS7 cabin character

The roles reverse once you climb inside. The BMW is the more overt and expressive of the two, featuring glossy red thumb controls, bright speaker grilles and ambient lighting. That is entirely appropriate: an M5 ought to feel sporty in the cabin, and it does, particularly beside the Audi’s sleek, near-monochrome interior, where the steering wheel’s discreet RS button is about as flamboyant as things get.

The problem in the BMW is its sheer physical size. Sitting in it recalls being eight years old and scrambling into your father’s car: the seat engulfs you, while the steering wheel seems too large to hold properly.

That childlike sensation lasts precisely until you begin using the displays, at which point you leap several generations ahead into the role of a confused grandparent. The home screen holds 58 apps. How, exactly, are you meant to control and search through them while driving? The layout seems to offer little logic or hierarchy, and finding the driving-mode screen merely reveals another set of bewildering options. Things were not like this in my day, and so on.

The Audi is five years old and one generation behind, so its graphics are less showy, but at least its functions are understandable. BMW once produced the best instrument dials in the world; surely it could have found a clearer way to display information. The new M5 is an exceptionally complex car to use. You can, naturally, simply get in and drive, but extracting the best from it requires understanding every part of your new car. That will take quite some time.

Weight, control and response on the road

Anyone who has read about the M5 before will probably recognise the phrase “disguises its weight well”. It does exactly that. Its suspension management, traction, initial turn-in grip and responsiveness are profoundly impressive. At first, it does not behave like a 2,435kg car.

Look beneath the surface, however, and you begin to identify what is absent: the secondary messages. The steering and brake pedal offer little feel because both are so heavily assisted, leaving limited opportunity for useful information to return to the driver. If the M5 loses composure on a slippery road and starts to slide, you will gain a thorough understanding of momentum.

Before that happens, however, the M5 possesses a degree of control and ability that the Audi cannot equal despite weighing several hundred kilograms less. It tackles a challenging road with remarkable composure and assurance. Its rear-biased four-wheel-drive system feels natural and communicative, firing the M5 from bends as neatly and accurately as it entered them.

The Audi follows in the BMW’s wheeltracks like an eager but easily distracted Labrador. Its steering has a springy quality, making a precise apex difficult to achieve. Apply the power again and the four-wheel-drive system sends bias forwards, inducing torque steer that tugs at the wheel and makes it harder still to maintain your chosen line.

Its suspension also moves more and controls less. It needs longer to settle, which can turn progress over broken roads into a continuously unsettled churn unless RS mode is fully engaged. Then it feels as though the dampers have received a Hollywood facelift, stuffed with so much Botox that nothing can move at all. Overall, it is less thoroughly resolved and lacks the BMW’s sense of expensive engineering.

As a destroyer of autobahns this new M5 has few peers. That’s what it feels like it has been designed to do

Crucially, though, the Audi understands enjoyment. It may be less capable, less tidy and more unruly, but its twin-turbo V8 howls beautifully while the tyres scrabble for traction and you work to keep it all pointed in the intended direction. You are not merely busy; you are entertained. It has more personality, energy and charisma.

You may assume the BMW’s hybrid system is its weakness in this contest. It is not. Instead, it improves the M5 with immediate reaction and a hit of instant torque. The effect is especially noticeable if you hold the gearbox in a tall gear and catch the engine below boost. The difficulty is that the heavy car is controlled so tightly that it has too little freedom to breathe. The M5 attacks, but it does not flow. It suffers from another Hollywood issue: cinched so tightly into its costume that moving risks something bursting. Put simply, it is too uptight.

The V8 is also too subdued. The Audi erupts with a yelp, then barks and rumbles, while the BMW sounds more restrained. It is slower than the RS7, too. That may seem odd given its enormous advantages in power and torque, but this is where the new M5’s weight matters, along with its inferior power-to-weight ratio not only against its rival but also against the previous M5. This is among the very few cars that is genuinely slower than the model it replaces.

Do not confuse that with being slow. During our testing, it delivered precisely on its claim, reaching 60mph in 3.44secs. The Audi, though, was 0.3secs quicker, while the old M5 was one of the rare saloons to slip beneath the three-second mark, even if only by 0.01secs. Only at very high speeds, when aerodynamic drag becomes a greater obstacle than mass, does the new car pull itself back into the contest. It lacks the low-speed urgency we want, but few cars can match this M5 as an autobahn destroyer. That is plainly its intended role: to crush Germany beneath a heavyweight fist.

The counterpart is braking distance. Physics, unsurprisingly, remains undefeated: the M5 stopped from 100mph in 91.56 metres, while the RS7 needed 86.22. The driving experience matters far more to us than a collection of dry figures, but these results illustrate BMW’s predicament, adding complexity while reducing tactility.

Efficiency, price and the final verdict

The ability to travel a worthwhile distance electrically is welcome, with BMW claiming 43 miles, but once you discover that it draws electrons at only 11kW, you are unlikely to stop specifically to recharge. Long cross-continental journeys will therefore involve carrying plenty of unused hybrid equipment. BMW nevertheless says the M5 can return 27.7mpg without the reassuring help of electricity, significantly better than the RS7’s 23.2mpg. In our test, the BMW averaged 28.8mpg overall and the Audi managed 18.3mpg.

There is further positive news for the BMW. Given its technology and the standard of its execution, £110,500 seems conspicuously good value. That is especially true beside the £125k Audi asks for the RS7. It can command that because the RS7 is such an attractive car.

It wins this comparison as well, because despite its price disadvantage it is better looking, simpler, more involving and more charismatic. If your preference is a purely internal-combustion super saloon, it is one of very few remaining choices. The RS7 now feels almost like a remnant of another era. Had it faced the previous M5, though, I am fairly sure it would have lost.

Does that put BMW on the wrong path with this new car? Not necessarily. But did its weight truly need to increase so dramatically? More significantly, despite all of its capability, the M5 feels as though it has changed direction, targeting an audience that is a little less focused on driving and a little more interested in luxury. Make no mistake: for better or worse, others will...