Be sure to look at Astral buoyancy too. We've been wearing their stuff for distance racing and they're some of the best life vests I've ever owned.
http://www.astralbuoyancy.com I have the Astral Newton partly based on Jake's suggestion, well, mostly based on his suggestion and it has worked very well. Unlike all the others I have worn, I forget that I am wearing it. However, it is not USCG approved. It is a "bouyancy aid"
