Just a follow-up: there is a better way to attach the clean bottle to the Sawyer. Just as they said, there is such a thing as a tornado coupling - I found a teacher's supply store that carried something called a Tornado Tube; it's used to attach two water bottles together to demonstrate the vortex effect. It screws securely onto the filter, weighs about half an hounce, and attaches the bottle firmly in place (unlike the Platy Link, which used a short tube that allowed the bottle to flop around.)

I'm gonna give the Sawyer filter another try; it's just too good an idea not to work.