@Gategate  Hey!  Thanks for asking.  It can be scary to try a brand-new thing on the trail, especially for something as important as Water, without first getting some feedback!  I'm happy to offer my experience.  I used the Sawyer Mini system for an AT thru hike a few years ago and continue to use it on the trail even now.  The filter itself is the same exact one, but the bag did eventually spring a leak.  I don't look at that as a ding, though.  This thing worked hard every day over many months for me!  It screws in nicely to the filter and squeezes well if you drink straight from it through the filter.  As I continually rolled and unrolled it and squeezed it into my pack pockets haphazardly, the first thing to go was the blue printing on the outside, but that was just cosmetic and I kept using it until it began to leak.  It is compatible with other brand bags as well.  The Sawyer Mini is NOT universally compatible with all water bottle threads, though.  Smartwater bottles work great with it.  There may be others, but test before you get out there.  Also, the soft-sided Sawyer bag (really any soft-sided bag) can be difficult to fill in shallow standing water, so some sort of a scoop can be useful to have along for those situations.  Or just use the straw attached to the filter to drink straight from the source at times like that, bypassing the bag.  

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