My experience is different than clasher's in that I find studded tires indispensable for SW Ontario winters. They've kept me upright more times than I care to count. While I concede that there are many winter days that studs are unnecessary, it's nice to know they're there in case Mother Nature decides to throw a curve ball while my bike is locked up, and I have to ride home in icy conditions. The narrowest studded tires that I'm aware of are the Nokian A10 which are available in 32mm width. Personally I use the 35mm Shwalbe Marathon Winter tires.