I got to drive the demo from my dealership this weekend. They let me take it out alone, which was hugely unexpected. I have to agree that the power delivery feels much different than that of my 335. The 335 feels faster around town because of all of the low end torque, however, once you get the m3 above 5000rpms, it screams.
The clutch pedal in the m3 is extremely light; I was expecting it to be heavier than my 335's, and it is far lighter.
Another one of my main concerns with the m3 was answered. I was highly sceptical about the servotronic steering being less enjoyable than the steering in my 335. It is very light in normal mode, but feels nice and hefty in sport mode. Just seeing the car in person was amazing.