And it still sounds like an M5. Regarding the top speed; I wonder if they fixed the C7, since it also reached a ridiculous top speed.
Unrealistic top speeds aren't related to some cars. The whole (aero) physics engine is incorrect, and it affects ALL (road) cars which are powerful enough to reach higher top speeds (300kph/200mph +).
So this issue is for BMW, and MB, and Ferrari and Corvette, etc,etc.