Not trying to persuade you one way or another but IMHO the Gerber LMF II has nothing to offer over the knives you own already. If you're happy with the USAF knife and mini Kabar both are at least equal to the LMF II if not better as far as a heavy duty, medium-sized belt knife goes.

Though of course you're fully entitled to buying a new knife even if you don't really need one. I have about a couple of dozen "utility" knives right now and still feel the urge to get me a new toy to play with every once in a while.

Anyway, the SEAL Pup would be a pretty good choice too if you like combo/serrated blades. A friend of mine swears by it. While not a hardcore user he's had that knife for a good many years now and still loves it.