JADP, but on the Japanese market, where tankless once ruled, everybody is switching over to heat pumps with 300 liter tanks so that they can take advantage of cheap off-peak electricity. The late night electricity costs about 1/6 of the daytime rate. These units start at about $2000.
People with RFH or otherwise heavy demand for hot water will install one of Honda's gas-powered Micro CHP units, which at current gas rates is competitive with a heat pump and will provide nearly as much heat on demand as a tankless. These are about twice the price of heat pumps. The Micro CHP has a generator built into it that runs off the waste heat that would normally be lost, and the advantage of this is that you get to sell the juice you generate to the power company at peak-rate charges, retail, and this is a big advantage if you are running the RFH flat out during the day.