Love my Camelback!!! I live in Houston and couldn't survive summer riding without a Camelback. I bought a new one this year and it seems to provide better ventilation on my back than the smaller one that I had before. (The design and materials are a bit different.) I fill a 70 oz Camelback with ice and then water and refill it from bottles during rides. It is amazing how long the water stays cool. I just empty it after rides and hang it upside down with the cap open.