We had been using a pitcher for about a year, and decide to get the 23 cup dispenser.  We are very happy with it: easier to refill, and there is always enough filtered water available, which encourages better hydration.  Overall, we are quite pleased with Zerowater filtration; when we lived in California, we had an under-the-sink reverse osmosis system, but when we moved to Massachusetts, we learned that the iron in the local water would likely lead to problems with a reverse osmosis system.  Zerowater is a very good alternative!