I prefer fixed gear and skinny tires for winter. I have the luxury of 3 bikes to choose from, and we generally dont have frozen rutted snow roads here. This year i have 23's on my fixed gear, will run studded tires on the mtb (I run it fixed gear for winter) and cx bike with 25's for nicer/dry days. The majority of the roads on my commute are plowed and dry, Toronto salts the hell out the roads so I stay away from a bike with lots of parts. I find fixed best as aside from normal winter maintenance like repacking bearings etc i dont have to worry about the salt ruining the cassette, deraileurs, and the salty road grim destroys rims. At the end of the winter I remove the chain, dip into a garbage can and let go. I prefer skinny tires to cut through the fresh snow and slush, I hate the the "floating" that fat mtb tires give. I find I have almost no control over the bike. I have no preference over drops vs. flat bars. My cx and mtb both have wide flared drops and the fixed gear has wide flat bars with bars ends.