2015 Mercedes-Benz S65 AMG Coupe UK first drive

It's currently the most expensive car in the Mercedes-Benz range, the AMG-fettled coupe version of the firm's trend-setting S-Class.

Providing the muscle is a colossal twin-turbo 621bhp 6.0-litre V12 petrol engine. Of course, 621 is a big number, but 1000 is bigger, which just so happens to be the amount of torque in NM at your disposal. 

Sure, S65s and big numbers go hand in hand, but surely even the most laissez-faire oil baron can't ignore the huge escalations in price across the Coupe line-up. The jump between the £96,000 entry-level S500 and £125,000 S63 might seem steep, but, for an S65, you'll need to find another £57,000.

Upgrading from eight to twelve cylinders doesn't have a dramatic effect on drag race performance, either; the S65 is just 0.1sec quicker to 62mph than the S63. Rather, the extra cash brings a unique front end, more standard equipment and the knowledge that you have the biggest number possible on the boot lid.  

An incredibly capable car, as long as you aren't expecting the final word in dynamism. AMG might have waved its magic wand, but it was never its intention to try and turn the S-Class Coupe into a sports car. 

That's not to say it's useless, because entering corners at speed reveals decent grip, and, as long as you have the suspension in its Sport setting (one of three), a surprisingly well-behaved body. 

The problems lie with the steering. It's a heavy car, this, and it feels it when trying to tuck the nose in to bends, while the steering never really weights up enough to give you confidence. The lack of feedback is almost a given.

Switching the chassis to AMG's Dynamic Curve mode actually helps lean the car into bends before you reach them, but the end goal isn't greater cornering speed, says Mercedes, it's enhanced comfort. It works reasonably well, helping to quell some of the pendulum effect this two tonne Mercedes suffers through fast chicanes. 

That said, even when dialled right back to Comfort mode, the S65 picks up on rivets and broken Tarmac a little more readily on its standard 20in wheels than the lesser S-Class Coupes, and certainly more than an S-Class saloon. Mercedes' impressive Magic Ride system seemed to miss more approaching speed bumps than with the saloon, too. 

The S65's power delivery is more suited to GT continent-crossing than precision back-road blasts, too. Stamp on the throttle from stationary with the traction control switched on and it's a case of computer says no, as it tries desperately to divvy up the huge amount of power and torque. The result is squirming and dithering for the first second or two before the power is put down.

Of course, switch the traction control off, and the rear wheels will spin until their tyres flail away. No, where the S65 is best is from a rolling starting. On the motorway, you can simply pick a car on the horizon, squeeze the throttle and fully expect to be overtaking it before you've chosen which type of massage you like from the driver's seat. Also to be expected is around 15mpg. 

Indeed, if the S65's performance is staggering, its cabin isn't far behind for wow factor. Its quality is some of the best you'll see anywhere, and the standard front seats are some of the most comfortable and adjustable it's possible to sit in. They'll heat you, cool you, focus on massaging your shoulders or your lower back if you so wish.