Road Test: Audi RS7 4.0T FSI V8 Bi-Turbo RS7 Quattro 5dr Tip Auto

Coincidence, said Albert Einstein, is God's way of remaining anonymous. In which case, we've spotted you, big man upstairs. For, just a couple of months after BMW released its 552bhp V8 twin-turbo four-door-coupe-saloon, the M6 GC, Audi has unleashed its own 552bhp, V8 twin-turbo... well, you get the picture.

Of course, the RS7 was not unexpected. It is, in essence, the RS6 Avant repackaged in a slipperier, squashier package - equipped, naturally, with the same 4WD and dizzying array of differentials and gadgetry. And, like its estate-bottomed brother, the RS7 boasts an entirely ballistic turn of pace, carving great chunks out of the horizon with every injudicious stab of the right pedal. Officially, it'll do 0-62mph in 3.9secs and, with the right option boxes ticked, 189mph.

There aren't many 550bhp cars you can treat like a Corsican hire car, but the RS7 feels virtually idiot proof. Jam the brakes mid-corner, barrel into a hairpin 50mph quicker than you meant to, whatever: the big Audi smothers all your stupidity under a great blanket of electronic cleverness and relentless grip. It's a freakishly effective machine for getting down just about any road at near-unimaginable pace, instantly transforming you into a far better driver than you truly are.

There is a trade-off. Like the RS6 - like every hot Audi - the RS7 isn't the last word in feelsome handling. In fact, it's barely in the second half of the dictionary. The steering's hazy, and trying to ascertain what's going on with the tyres is like playing the piano in oven gloves. Ride quality on the steel-spring suspension offered as part of the Dynamic Ride Control package is disturbing on a deeply psychological level: better to stick with the standard air suspension and save your cash for the optional carbon-ceramic brakes, which do a reassuringly pitiless job of hauling the RS7's near-two-tonne bulk to a halt.

However you spec it, the RS7 remains less responsive and interactive than that pesky rear-wheel-drive BMW M6 GC (which, admittedly, starts some £14,000 above the Audi) or the thunderous, similarly slidey Mercedes-Benz CLS63 AMG. But if you're happy to trade in drama and involvement for devastating, accessible pace and a dose of flattery, the Audi is king.

Still, if we were in the weirdly specific market for a 552bhp hyper-Audi, we wouldn't take the RS7. Our 80-odd grand would still go on the RS6 estate, not only for its capacity to transport an extended family of Weimaraners, but because somehow the estate makes more of the pair's slight dynamic shortcomings than the sleeker RS7. Sure, you think, it's a bit heavy and a bit distant and a bit leany, but, hey, it's an estate! Him up there - practical family man that he is - would surely agree...