I did, and now that I just installed a VF620 kit ..I can honestly say the M3 is now a better car all around. I do hear that awesome downshift sound with an xpipe and the M3 now hauls ass just like the GTR but with more fun of a RWD
The M3 stock was a lot left to be desired power and fun wise, but the M3 will always look sexier in my eyes.
If I had to compete in a million dollar track event then I'll choose to pilot the GTR, I can understand why a lot of people are leaving a stock M3 to C63 and GTR because I almost did too ... Until the catless xpipe and supercharger went in! Wow what a difference