I was recently in my local marine store and came across an inflatable life jacket by Mustang Survival. It's very small and unobtrusive and is inflated with an enclosed C02 cartridge by pulling a cord. I tried one on and it is VERY comfortable. It comes in black, red, or blue, and it turns yellow when inflated. It can also be manually inflated through an attached hose. It is Canadian and US Coast Guard approved. The cost is $150 (Cdn) which is comparable or just slightly more than most PFDs, and replacement cartridges are about $20.

Has anyone used one of these for paddling or know of any reason not to?
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