This Sawyer Micro Squeeze was amazing on several day trips where clear flowing water was prevalent. However, during archery elk season water sources were drying up and sometimes we had to get water out of a lake. In my 7 day trip this thing turned into being a very hard filter to squeeze water out of by day 3. My attempts to remedy this high-effort required by back washing did not improve the situation. I backlashed several times, using the precious clean water I had and it didn't' get better. As the week went by I talked to a Pacific Crest Trail through hiker who said--'get the larger size'. For what it's worth, my backup filter-- an old MSR MiniWorks, also struggled with the water we had available to us. If you have clear and flowing water, this'd probably be great.