I hiked 500 miles from Springer to Mt. Rogers last year. I started with a MSR Waterworks. It had worked well for practice hikes in Shenendoah, but soon as my wife and I got started in GA, it gave us fits. I swapped it out for a Katadyn Hiker at Neels Gap and never had a problem since then. I will use it again in a few weeks when we start our next 600 miles.
We also carry a very light weight water bag that holds about 2 1/2 gallons of H2O. One trip to the water source is all we need. It also lets the sediment drop to the bottom of the bag. When we are ready to pack up and head out for the day, I hang it on my pack to dry out.
Good luck and have fun. L&F
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