In the latest issue of "Canoe and Kayak" magazine, there is a short article on inflatable PFD's that use replaceable CO2 cartridges. I know it is relatively old technology but it looks like it has been given some updating. They give a brief description, the names of a couple manufacturers and a photo of a very compact example. I have a nice Stolquist PFD already but am interested in the technology. I will do some web surfing to find information from the companies that make these but wanted to get opinions from anyone who has personal experience with them. You all give much more objective insights than a company who is going to profit from unbridled praise of their own product. Any input would be appreciated. Many thanks.