Do your really check all your equipment before a tour? Set up your tent, get out the sleeping bag, test the pad, fire up the stove, make sure your fork is working properly, etc.? Testing a water filter before a tour is on the same level as making sure your fork is working. I've had a couple of filters over the years and never had to "test" them before use.

As for proper storage, I used my Sawyer filter once, as in a single time, as in not more than one, as in less then 2...this is staring to sound like the Holy Hand Grenade of Antioch...and after that single use I stored it according to Sawyer's instructions. I back flushed it, let it dry and put it in the bag. What more could I have done? What more would you have done? Testing a water filter before a tour is on the same level as making sure your fork is working

There is a whole lot of Monday morning quarterbacking going on in this thread about the Sawyer. Honestly, drying out the filter doesn't seem that extreme to me nor should I have expected the filter to become nonfunctional after a single use. I'm not the only person to experience this problem and, if I were to buy another Sawyer, I would test the damned thing before each and every trip. But I'm not about to buy another one because I would have to test it before every trip and I'd be worried if it dried out on me.