Last year, I rode 28's spring to fall (I use Nokian 35's in the winter), but I think that was too thin. I switched to 32's this spring. I have a Panaracer Urban Max on the front and a Soma New Xpress on the front. As far as I can tell, they're pretty much the same tire, just different labels. (Please correct me if I'm wrong.)

I like the 32's. As long as they're fully inflated to 95 psi, they ride fast, but they also handle bumps better than the 28's. The biggest downside is that I have to be more careful about monitoring tire pressure. My 28's could lose 10 psi without much problem (120 to 110 psi), but the 32's really start to get sluggish at 85 psi.