When I visited my cousin, my uncle and his family and my aunt in Japan, they all had those tankless water heater. I didn't notice any difference between the tanked system here in US and the tankless system used by my relatives.

I've been trying to get my plumber neighbor to install one. He is driving me bananas!!

My plan is to use solar water heater system using the evacuated glass heat pipes and use a 40 gallon? storage tank. Then use the tankless system as a back up. The idea is to use much of the solar as possible so that the tankless will remain off for the most part or only have to heat the water by additional 10-20 degrees instead of 60-80 degrees. This way I don't have to worry about running out of hot water in the evening.

So my patience is being tried...

Smilingcat