I used the filter this last weekend as a backup water supplier. Unfortunately, our GPS unit failed and we got lost in Southern Utah. This filter saved us. We were in a little slot canyon in Escalante and got a little nervous when our water ran out. The only water we could find was in cesspools that wreaked and were covered in a nasty little film and filled with bugs. Of course, the water didn't taste great, but none of us ended up getting sick. I was very pleased with it. Plus, the Nalgene attachment is kinda cool and convenient. It pumps water pretty efficiently as long as you clean it after every use. Oh, and it's way simple to clean. I couldn't have asked for more.