Truth: Auto-inflate life jackets are NOT 100% guaranteed to inflate. If you want that kind of guarantee, you have to wear a standard foam type PFD. What they are is a really good alternative to not wearing any PFD while fishing. While running your boat at speed, they're not a good substitute for a standard PFD. If anything happens while running at speed, there is much high chance of entering the water with an injury and the jacket may not inflate. Also, a standard jacket provides some level of protection to your body should you hit something. I have a standard jacket that remains attached to my kill switch and I have my auto-inflate for when I stop the boat to fish.