They were meant to be identical – the M3 and M4. You are not meant to be able to tell them apart; aside from the very obvious fact that one is a coupe and the other a saloon.
The F80 heritage lies in the generation of M3 models dating back to 1985. This time again, as a sedan, with a performance and pace that never was in doubt. The perfect combination. The perfect car.
A good car. Exceptional, in fact.