EsoxLucius - I see you are new to the forum so I will save myself some time and suggest you use the search feature if you are serious about your question.
Et Al - tankless work great for a subset of RVers who prefer to stay with full hookups. It does require a consistent flow of water and adequate sewage to be of any use. As noted in my comment we had their tankless unit on our previous rig for 3.5 years and absolutely loved it; it worked great and provided endless hot water. It was also efficient, only heating water when needed, plus it saves about 80 lbs of extra weight while travelling.
As noted this new unit seems to be a lemon and the company only stands behind their product in the sense that they are ready to send me piece by piece all the components rather than make it easy on me and just switch it out.
