It is definitely true that some tracks favor a classic front engine/rear drive layout over a more powerful but heavier AWD such as the Audi. A couple of points worth mentioning. As we know the 335i does not have a LSD. On a tight track the LSD would have a substantial effect on the cars time. Porsche admitted a LSD on the Cayman would make it faster than a 911 on many tracks!
Comparing the E92 M3 to the 335i, just on the chassis side, we will get:
-much faster/better steering, feel and performance
-less unsprung weight due to an almost full aluminum suspension
-better brakes and brake cooling
-stiffer springs, more performance damping (+EDC as an option)
-stiffer chassis overall
-much higher performance tires
Not even mentioning the engine, these things alone will offer a huge lap time benefit for the M3 vs. the 335i's already impressive time/chassis. The 335i is a fantastic starting point for the M3!