The inevitable conclusion of Mercedes’ every-engine-in-everything product planning – meet the improbable union of the vaguely MPV-ish R-class and AMG's 6.3-litre V8 motor. The result is the fastest six-seater in the world, performance constrained only by a 155 mph electronic speed limiter. The £74,115 price tag and 17.3mpg combined fuel economy are slightly less amusing.
What’s it like?
Better than expected, to be honest. The engine is very much the star of the R 63’s show – this is one of the world’s great powerplants - and the massive, linear performance is channelled through to the road surface very effectively by the R-class' four-wheel-drive chassis.
Autobahn cruising speeds are alarmingly easy to attain and, thanks to excellent cabin insulation, few cars feel more composed at mega-velocities. Off motorways and straight A-roads though, the R 63 suffers with roll-prone handling and lurid understeer in the wet. But then you knew you were going to read that somewhere in this review.
Should I buy one?
If you’re a millionaire with four kids, a second home in Geneva and a real life get-out-of-jail-free card for the French Gendarmerie, then it’s worthy of serious consideration. Otherwise, it's hard to rationalise how this car is really any more effective as a sports car than any other R-class in the range. In anything other than a very fast, very straight line, that is.