The authorities are always telling boaters to wear their life jackets, but most sailors only pass them out to their most helpless and inexperienced passengers, donning them themselves only as a last resort. This is especially the case with the standard, "approved model" which is primarily designed to keep an injured or unconscious man's head above water. For small craft, they are bulky, clumsy and uncomfortable, hard to move around in, too hot in sunny weather and unable to keep you warm in the cold. And it takes forever to put one on, or instruct a lubber how to properly do so. They are OK if you are sitting in one spot, at the helm or tending a sheet, but downright awkward and dangerous if you're scrambling around on deck or fighting for your life in some midnight battle with flogging sails. In tight quarters below decks they are always getting snagged on something or getting in the way.

For safety I recommend the zippered life vest type, not quite as buoyant, and not able to keep your head out of water, but easier to move around in and offering some protection from the weather. I am a firm believer in a safety harness, with a long clip-on lifeline equipped with a quick-release shackle or a carabiner. I'm a good swimmer, but if I go overboard, I can't swim fast enough to keep up with my boat, whether I'm wearing a life vest or not. And in my opinion, it's much more likely you'll go over the side accidentally than that you'll have to abandon ship on purpose with no advance warning.