MTR's
Although I'm currently running 35" BFG mt's I have already punctured the side walls twice and chewed part of the rim guard off on a branch. I wheel the Con' and Fordyce mostly. Abusive rocks, water and snow, w/ the occasional tree branch or stump. Great tire on the road, quiet and no wandering w/ pot holes or such. But, as it's been said, they have weak soft sidewalls. My typical pressure w/o beadlocks is 8-10psi. I have lost many beads and needed to air up quite a bit on the trail though. The G/Y MTR's seem to be a good quality tire, w/ stronger side walls. Good traction from what I can tell to date from seeing them on other rigs on the trails. As far as the drum stopping power, never had a problem, but I've got a good booster.
Good luck,
Campy