I always thought of the M-Coupe as the clown shoe. Now, that is not to say that it is one of the best cars that I have ever driven, but it is a very close second to a full Dinan E30 M3. I love the M Z3, but the Coupe feels so much more solid (especially on really rough 180 deg. switch backs). If I didn't have a family, this car would be in the top 5 of cars I want (that I can realistically own).
This is my #1 though. Full Dinan E30 M3 - including the stoker kit. My best friend had one of these while I was in college and having driven 100's of different cars, this is the best to me. Supremely nimble with a slight oversteer on throttle, stiff, powerful (240 bhp), and still looks good to this day.