When I ride my SS MTB on the road I use 32/14 with 2.1 Panaracer Fire XC's which according to Sheldon Brown gives me a 59" gear. With my fixie I plan on 46/18 with a 23-25mm tire which is a 67" gear. Any idea how these 2 would compare? Would the decrease in rolling resistance make up for the bigger gear? With the MTB the 32/14 is great around town unless I get a strong headwind.