Well, there's a lot of factors here, most summarized by its exact model: It's an M1045A2, Marine Corps slantback configuration. It's "more awesome" than a regular HMMWV by being a weapon platform, has a deep water fording kit installed, the engine is the 6.5 by design, the transmission is a 4 speed 4L80E, and the chassis is rated for a heavier load. For road usability, it has no "off road only" restriction, making registration much simpler in most states. I have a feeling that most of those other HMMWVs were M998, M1038, M998A1, or M1038A1 trucks, which are lighter troop/cargo trucks that typically have the DLA "off-road use only" restriction applied to them, which keeps the prices from going too high.