23c Ultra GatorSkins have handled everything NYC streets can throw at me on my fixed gear. Rocks, glass, expansion joints, dirt, cobblestones, nails, razor blades, bodily fluids, needles, salt, sand, dirt, grass, car parts, broken plastic...pretty much anything you can imagine (and some you can't). I bought them for my fixie as I spend alot of time spinning miles out in the city but I adore them so much I bought a second set as a training tire for my carbon fiber roadie.

Great tire. Not the lightest...but not the heaviest. Fast rolling (in either direction) and good traction, It is a bit iffy in cold temps (under 15F) but what tire isn't and in heavy rain you'd be best to be mindful (but what tire shouldn't you be sans a full wet tire)....