I got away with running all seasons in the winter for the last few years with my STi.
Now with the 335i, buying Winter Tires/Wheels was the first thing I did.
07 SG 335i
COBB - Burger Motorsports -Ultimate Racing - Evolution Racewerks - TiAL- AMS
In Winter Mode - Dunlop Wintersport 3D/Sport Edition Wheels