Of all the PFD's mentioned, only the Stohlquist one is class legal for Hobie racing in North America because it's the only one that's USCG / Transport Canada approved. The Salus Abacus looks nice, but it's only Transport Canada approved.

The Gill one is a "buoyancy aid" and is not legal for Hobie Class racing.

BTW, I second Mike's comment about straps and buckles. My Extrasport has three on each side and is always catching on something if I don't wear a rashie over it.