Bests & Worsts Reviews from Amazon

So, I was really excited to use this filter on our backpacking trip. The second day of the trip, I became completely disillusioned by this filter system. When I received the system, I read through all instructions and followed the initial use instructions to the letter. I then used it for the first time at home to actually filter water to ensure I knew how to use it prior to going out backpacking for several days. The water tasted clean and I felt we were good to go. Once out, we used it multiple times the first day to refill our hydration packs. The process was a little time consuming and takes a bit of effort, particularly if you have smaller hands like me. However, the water continued to taste fine. Fast forward to the second day. We refilled our hydration packs in the morning and started out. I took several big gulps of water and realized my water tasted horrid! It had an awful taste to it. It's hard to describe, but it was bitter, almost as if you had allowed a Tylenol caplet to begin dissolving on your tongue - just outright horrible and concerning! I spit out the remaining water and asked my backpacking partner if she had tried her water yet. She tried some and had the same reaction. We were mystified, as the water the previous day tasted fine. We hiked to another stream and refilled there, thinking maybe it had to do with our water source - which was doubtful as it was clear spring-fed water, but we weren't wanting it to be the expensive filter we had just purchased. Unfortunately, this tasted even worse! And yes, we squeezed the bottle back and forth thoroughly for the whole 10 seconds that the directions specify. We then took the micro squeeze portion of the system off and attached it to a 1L squeeze bag we had and drank from that. That water tasted absolutely perfect. This leads me to believe something was very wrong with the foam/bottle portion of the system. We were so disappointed! I called Sawyer customer service. I wasn't given any information on what could have caused the problem, nor any resolution.