I ordered this product, not sure of the end result - but confident in the reviews I had read and the experience I have had with this brand. The install could not have been easier. I connected the lines, flushed the system, connected the gas, connected the remote unit. I then turned on the water and the gas. It worked the first time, it heated up quickly and more than hot enough. Additionally, I had to run water lines from my attic down to the side of my house (where I wanted to install the unit. I added no less than 25ft of additional line to this unit than was connected to my existing attic tank water heaters. Nevertheless, the lag time to hot water is nearly identical! This was as seamless and easy as I could have anticipated. I do recommend a professional for the gas line hook ups, to make sure you are connecting properly and with sufficient BTU's.
Lastly, delivery from CPO was much faster than anticipated! It arrived a day before my window was supposed to start! Though the front of the unit was damaged in shipment (not CPO's fault) it still worked fine. Better packaging is desired as I know I'm not the only one to have a damaged unit upon arrival.