I partly agree. I think its fine to use hydrostatic vest up to 60 mph. Above that the water and speed together can be fatal. Check out Crewfit 290N Advanced & Advanced Plus at http://www.crewsaver.co.uk/Crewsaver....html?catid=95
The god thing about these vests are that they have leg straps. Without the vest tend to go over your head if you hit the water at high speeds. Just something to be aware of.