IPSC (which is USPSA.COM in USA) requires a belt go through the belt loops. HOWEVER, you can use an "outer belt" velcroed to the inner belt. Why bother? If you use a holster (other than a paddle) its a pain to always put it on & take it off just to practice & shoot every weekend. Besides, the holster & mag pouches are never quite in the same place from day to day. Pracitce with it in one spot & it won't quite be there next time.
The 2-piece belt is common in all Divisions of USPSA including production. Mount the holster & pouches on the outter belt ONCE & they are always there. Belt comes off in seconds without your pants falling off.
I have both a safariland gunfighter and a CR Speed Hi-torque system belt; the CR speed is far supperior & it even costs less!! Brownells has these as do many of the vendors in the USPSA monthly; Frontsight. This is the belt you want.