From what I understood a water filter is usually okay to use in the US. I bought a msr miniworks for my hunt in UT in September, but I see everyone mostly using purifiers now. Has anyone used the miniworks? If it works fine I was think about keeping it and using the steripen to double tap the water make sure it's good. If not, I might just return it for the sweetwater purifier. I want to stay light but I don't know about just the steripen I would like the water pre filtered before drinking it.