OK, we will agree to disagree on who the respective cars are competing for, because for 1 they are competing for me.
2, I am not aware of any"official" track comparisons between a slightly modded 335i and the e90/92 m3. There is a guy with a Dinan modified 335i, reported to be an experienced racer, over on e90post that reports beating Porsche GT3's and Vette's at Laguna. If that's the case, then the M3 will suffer the same fate.
http://www.e90post.com/forums/showthread.php?t=108953
Interesting thing is this is the first guy who has reported an issue with the brakes, but based on his racing resume also may have flogged the car the hardest or been on a heavy braking track.
Like I said, we'll know more this year.