I think this test is probably the most fair since its the M3 saloon vs the C63, you can forward to about 3 mins where a german driver takes them both to the track:
http://www.youtube.com/watch?v=TdCpxC5Wn2w&feature=related
It might be old but i loved it!
Note: In top gear they compared the M3 coupe vs C63 on the track, hence why the M3 won (imo)
http://www.youtube.com/watch?v=TdCpxC5Wn2w&feature=related
It might be old but i loved it!
Note: In top gear they compared the M3 coupe vs C63 on the track, hence why the M3 won (imo)