Originally Posted by Papa Tom

I just bought two of these for my weekend trip after reading a bunch of glowing reviews. The REI salesperson told me I could expect to have cold water several hours into my 50-mile ride, which seemed ridiculous because I knew I'd already be on to my second or third refill by then. I decided to give them a shot anyway.

The bottom line? I'm not too impressed with the performance of these things at all. Essentially, they didn't seem to keep the water any colder than any five dollar bottle I've ever owned.

Has anybody else used these?