Originally Posted by ManiacGT
You need to do much more research, they're completely different cars.
The C63 is track focused, incredibly powerful/torquey and with an earth shattering sound. But IMHO its not an everyday car, it's just too uncomfortable (hard ride).
The Z4 (e89) does not have an M version (M sport pack is a token mainly superficial thing) and is not track focused its an everyday car you can also have fun with.
correct, c63 is compared with m3, z35is is less agressive but you get 2 in one (vert)