I have the same problem with leather belts warping over time. I finally found a belt that I like that can take a beating. The belt is a Looper reinforced holster belt. It has a leather outside with a reinforced Kydex interior insert that keeps the belt in its form. I have been wearing the belt for almost a year and it has held up just fine even with my Leatherman Charge TTI looped onto it. The only problem that I have had with the belt is that I sometimes clip my Surefire to the belt and that has scratched the leather a little bit. But now that i think about it they may have some kind of a warranty on the belts...

Just do a search on Google for "Looper Leather" and you ought to find them. They are based out of OKC.

I think they are primarily used my Law Enforcement that require a good strong belt.