After having my own Nalgene bottle equipped with Epic Filters for a couple months now I finally caved and bought my girlfriend one too (so that she would stop stealing mine all the time lol).
Love this water bottle. For starters, the design is wonderful. The filtered water tastes great, and there is no delay in the filtration. I have only had the bottle for a week now, but so far no leaking or malfunction of either the filter or the bottle. Recommended to family and friends as well!