I've used the Schwable Crazy Bob tires on my Trek 930 on some pretty rough stuff and it has handled well. The only thing I didn't like about the tire was that it had a lip that extended over the wall of the rim which reduces the brake contact patch considerable. I cut it off with a razor blade and the tires have been great. I've wondered about the others listed mainly the Holly Roller, and K-Rad. Probably will try one of those next.