Another water filter I have is the http://www.nitro-pak.com/water-storage/water-storage/water-filters/katadyn-ceradyn-drip-filter, it is in daily use and I always keep 8 gallons filtered in the new style water containers. I cycle through this each day and replenish as soon as two gallons has been used and then I cycle the new stock behind the old stock. Easily produce 4 gallons a day of safe water. I have this in daily use since 1998, same filters with a monthly wash down of bleach.
