Product review (1 stars): It leaks pretty badly when not properly sealed
The o-ring that comes with the filter is much too large for it, but the filter will not be usable without an o-ring. It leaks pretty badly when not properly sealed. Luckily, I had a spare, smaller, o-ring lying around and everything worked out just fine. Nothing leaks and the water tastes fine. I'd definitely buy it again, even knowing that I have to supply my own o-ring. It beats paying the retail price.

Update: It started leaking about 2-3 weeks in and wouldn't stop, no matter what was done to it. I just decided to buy one of the legit ones from the manufacturer. More expensive, but they don't ruin everything with water.