used to race mountainbikes with usd forks. the aluminum ones stuck like hell. tolerances are really tight and over clamping the tubes is a major potential for issues. I know for a while the mechanics were crazy glueing the interface and doing the bolts little more then finger tight to get by. also the lack of a lowerbrace causes lots of twisting, which prevents the stansions from traveling freely. they look cool though, i'd run em.
on a mission