I convinced my wife to hold off on buying me Xmas gifts I don't really need but instead convinced her that we need some basic survival stuff for our future kayak and hiking trips. So, one of the basic items I told her we need is a portable water purifier. I perused recent catalogs from REI and Campmoor that came in the mail and saw a number of models with varying prices, although performance differences were subtle (I suspect that is intended by the advertising departments). So, I'd like to solicit the gang's opinions/recommendations on models considered great reliable values for the money. Thanks. ...Paul C.