I bought several for our family. My SIL and I use them occasionally. I've probably run 80 gallons through mine so far without backflushing it and no apparent change in function. Considering what I spent on a Katadyn Pocket filter which has considerably less capacity and is quite a bit heavier and larger, I'd say the Sawyer is a great value for the money comparatively.
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The ultimate result of shielding men from the effects of folly is to fill the world with fools.
-- Herbert Spencer, English Philosopher (1820-1903)