My wife and I have been using Zero Water filters for 8 years and it is the only water we drink. We fill up bottles if we are going on a trip and we never have to buy anything on the road, and why would we want to? There is no water available out there that is as clean and pure as what we get at home. The filters last us a long time as we only use it for drinking water, I have figured the actual cost to be less than $0.25/gallon which is incredibly cheap compared to purchasing bottled water and of course I am happier with this water over anything we would buy.