Parsimony is probably not the AMG buyer’s primary motivation. Nevertheless, better efficiency is one of the key criteria of the engine downsizing effort, and no owner will complain about gains in economy.
The latest C 63’s official claim improves on its predecessor’s paltry 23.5mpg by a full 11mpg. However, even with a True MPG test not possible, we found ourselves still averaging about 19.4mpg, lengthened to only about 25mpg on a cruise. Better than before perhaps, but still well short of the 35.6mpg touring figure we managed in the BMW M4.
The emissions battle, particularly if you opt for the cheaper manual BMW M3, goes to the Mercedes – no small feat when you consider the relative cylinder count. However, choose the BMW’s M-DCT gearbox, as most buyers do, and the difference is inconsequential.
Given that the C 63 proved slower than the two-door version of its chief rival in our hands, it’s hard not to recommend the S model right out of the gate, which penalises running costs only very slightly in return for an extra 34bhp and 37lb ft, not to mention larger wheels, bigger brakes and better front seats. But then you’re forking out £10k more than you would for an entry-level BMW M3.