I have one and installed it myself even. wouldnt you know it still works and has no trouble filling the 80gallon garden tub I also installed. Works well, could it be better and more on demand yes, however you would also need a recirculating pump to allow for you to have instant hot water whenever you turn the faucet on. Otherwise as I have without one, it takes 30 seconds or so of running the water before the lines fill up with hot water. Kinda trivial-co but its a $500 difference that I didnt care to spend of mess with and can always install later on. And with that there is maintenance involved as well, as once a year, much like a tank heater you should be inspecting and cleaning those parts to keep it working most efficiently. More so the worse you water is, as in sediment, calcium, iron and whatever else you might find in typical city treating water or even countryside water wells which can be a bit harder. NOW I have a natural gas unit in the city house which was more feasible then if I had to run propane. Which they have great smaller units you can install directly under the sink vs the whole house. Myself I have a whole house unit and got a great deal on it at the time. So was worth it by far for me. Mainly the usage is most important for deciding to install a tankless. If you use hot water a lot and perfer longer hot water use then Id suggest going that route. I went that route based of the need after installation of garden tub and not even being able to fill it half way before hot water ran out. It costs some coin up front, but overtime you get that back or get your money's worth.