It is important to understand that M3 throttle mapping is different from most cars out there. It is so linear, without that exaggerated initial surge, that car feels slower than it is. The first 5% of pedal movement gives the same torque increase as the last 5%. In contrast, in 335i the first 50% of pedal movement has like 80% of the torque, if not more, and in rental toyota matrix I was getting probably 95% of available torque from 10% of pedal move (the rest of the gas pedal motion seemed to only change shift points for the auto gearbox)
Simply speaking, to feel the power of M3, you need to push the gas pedal further than in most other cars - preferably all the way in. My wife's reaction to M3 after 335i was - "it does not go", but now she is doing burnouts on every other stoplight
and that's with DCT set to the second mode (the least aggressive one I'd consider using in summer)