Pirelli and Michelin tend to focus more on the handling aspect of their perfromance winter tires, where Bridgestone focuses more on the snow traction. Dunlop is generally in between. Over the years this can change as new versions come out, but for 09, and the recent past, this has been the case.
Without knowing your wheel setup for winter, it is hard to say what is available, so if you have a specific sizing question call me at 800.428.8355 x660.
Subw00er, it sounds like you are looking for better handling than the Dunlops, so the Michelin or Pirelli would probably be your next step.
I have accepted a new position at Tire Rack and am no longer in the sales department. firstname.lastname@example.org
is available to assist with M3 questions.