Just wondering if any body out there has been installing any of the instantanous electric water heaters. I see that some of these require 120 amps. I realize that these would have to be subdivided. Wondering what the payback period is because of the initial cost and having to increase the size of the service. I know to calculate the payback period you would need to know how often it is used. But just wondering what some of you guys thoughts are. I would imagine that utility company would have to set a much larger transformer if supplying a large commercial building with several of these or if feeding several houses that had these installed.