If money is no option buy the M3 and a nice used 328xi for the winter.
Snow shouldn't ne am issue though. I have only a 330i and with snows its awesome in the winter (And we get more snow than you do). It's better in the snow than my Subaru wrx was quite frankly.
330i ~ BMW Perf. Susp. ~ M3 Front susp ~ BMW Perf Exhaust ~ 3.38 lsd ~ SF71 Alf CSL reps ~ Pilot Super Sports ~ AA Tune ~ 335is front brakes ~ EBC Yellows ~ 160,000 miles hardly broken in! WTB: e93 M3 Front Sway Bar