When I got my Fisher, I realized I was likely going to be riding it on pavement for the most part. About as far off-road I would get would be the occasional recreational trail paved with packed limestone screenings (a la Elroy-Sparta). I got a second set of wheels for it, with slightly narrower rims, and put 1.5" tires on them, and they've been great. I kept the OEM wheels and knobbies just in case, but I've never ridden on them. Maybe when I get the new road bike, I'll switch the Fisher back over to its original configuration and use it to explore the off-road world a little more. But for now I'm extremely happy with the 1.5s. They seem to give me the best combination of (relatively) little rolling resistance and the extra versatility and cushion of a tire that's wider than most 700s.