The Audi RS7 is now offered in even more potent form. For around £6500 more than the standard RS7, this Performance version gives you an extra 44bhp and 37lb ft more torque from its twin-turbocharged V8 petrol engine, taking the totals to 597bhp and 553lb ft.
The standard RS7 isn't exactly slow, but with this upgrade Audi claims it can now charge from 0-62mph in just 3.7sec, an improvement of 0.2sec over the regular RS7. It tops out at an electronically limited 155mph, or you can pay more to have that figure raised to 189mph.
Also included over the standard RS7 are larger, 21in alloy wheels, a more raucous sports exhaust system, a drive mode select button on the steering wheel, more privacy glass and blue stitching on the RS7's sports seats. A Titanium pack is also standard, which turns the RS7's lip spoiler, mirrors, diffuser and air intake ducts titanium grey.
What is the 2016 Audi RS7 Performance like to drive?
Audi's 4.0-litre V8, which it shares with other Volkswagen Group brands, remains one of the most impressively brutal engines on sale. True, you'd be hard pushed to feel the Performance's extra output on the road, but planting your foot hard on the accelerator begins an almost instant and seemingly relentless wave of power that pins you to your seat.
The sound from the RS7 Performance's sports exhaust is fantastic, too, turning from a burble to a bellow as the revs rise and crackling on upshifts and when you lift off the accelerator. Changing gear can be done manually via paddles behind the steering wheel, and in the most focussed Dynamic driving mode, the changes happen milliseconds after each pull.
Many buyers will consider Audi's optional £10,725 Dynamic Package Plus, which unleashes the 189mph top speed, adds longer-lasting ceramic brakes, changes the RS7's steering to a variable set-up (it gets quicker the more you turn the wheel) and swaps its air suspension for conventional steel springs.
Even without it, our car still proved extremely good at covering ground in both the wet and dry. The RS7 Performance has a massive amount of grip, and its four-wheel-drive system ensures that as the front wheels start to struggle, the rears begin to help. It's a shame, then, that the steering isn't particularly communicative, leaving you confident in rounding each bend, but never completely involved in the process.
Flicking the driving mode to Comfort causes the exhaust to die down and the suspension to move more freely, transforming the RS7 into a brilliant long-distance cruiser. Despite the huge 21in standard alloy wheels, ride comfort is good and, aside from some roar over coarse surfaces, the Performance's interior stays remarkably quiet at speed.
What is the 2016 Audi RS7 Performance like inside?
Much like the standard Audi RS7, aside from the addition of the blue stitching on the seats and the new driving mode button on the steering wheel. As such, two adults are able stretch out in the front, and another two (there's no middle rear seat) are able to sit behind, albeit with reduced leg room and head room that’s restricted by the sloping roofline.
The RS7's sweeping lines also make it a little difficult to see out the back of, although it’s easy to find a good driving position because there's a huge amount of electronic adjustment in the steering wheel and relatively low-slung driving seat. The RS7 makes do with an older version of Audi's MMI infotainment system; aside from its slightly more complicated menus and more numerous buttons, it remains one of the class's better systems.
The same goes for the interior, which has materials and switches you'll recognise from Audi's older models rather than its latest. That's not such a bad thing, though; everything still looks and feels brilliantly plush and sturdy.
Should I buy one?
In terms of straight-line speed, the Audi has both of these rivals beaten, and for less money than BMW charges for its M6 (although the Mercedes is cheaper). On the other hand, the BMW is marginally roomier inside and has a slicker infotainment system, while the Mercedes is more entertaining to drive.
If you do want an RS7, though, we reckon you'd be better off pocketing the extra £6500 and sticking with the standard model rather than the Performance.
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What Car? says…
2016 Audi RS7 Performance
Engine size 4.0-litre V8 turbo
Price from £92,060
Torque 553lb ft
0-62mph 3.7 seconds
Top speed 155mph (limited)
Fuel economy 29.7mpg
CO2 output 221g/km