I bought some cheap clamps off eBay for my Tiltalls, which live outside, unmanned. The only issue I had was a slight variance in tolerances on some of the clamps that prevented me from locking down some cheap eBay Arca plates. By moving up to Smith-Victor plates (A whopping $8 each), all the clamps lock fine.
The locking knob is really the only thing that can go wrong here. I tried removing one, but couldn't with any reasonable means.
That said, my personal preferences for daily use are the stock Arca-Swiss clamp on my B1 or the Sunwayfoto DDC-42i, simply because they're smoother and more comfortable to use.