I'd been using a Motorola H350 since release, with *very* limited success. Basically, it would occasionally turn off my controllers!
I've since bought some Sony-Ericsson thing, which is *vastly* superior. It was about £30 for a supermarket. I can't fault it to be honest.
Having done a bit of research ALL motorola headsets have connectivity problems with the PS3, so steer clear!
I had a motorola, the same model as you and it was rubbish.
USB headset for the win, always works and its more comfortable / better sound quality.