I find it doesn't slip at all, due to the way it grabs the belt. Can you physically make it slip if you grab it and pull from the belt parts not in the buckle? I understand for you it's a loosen-over-time thing, just trying to see if I can replicate it.

I really like mine as well, I haven't had it quite as long, probably a little over a year, but you really can't tell, it is not showing ANY wear. It might be an ad, but so many people chiming in with similar experiences kinda blows that assumption away a bit. The only thing I worry about on mine is the sealed/singed/hard edge where they cut it getting frayed. So far, so good though.