Tankless Water heater

I've installed one in the S&B. Love it but I would question why you want one in an RV. In a house they have a lot of plusses, but in a MH your enemy will be fluctuating water pressure and water source temperatures. The burners work on flow rate. The higher the flow rate the hotter the water. Also factored into the equation, the amount of power required to heat the water from it's temperature to the desired temperature - again static in a house, variant in a MH. You get to a CG or on the onboard water pump I would question the psi and varying temperature and subsequent ability to generate enough flow to heat the water and to what temp. If it dips below the minimal thereshold the system shuts off and the cycle will start again once psi comes up. You have to wait for that and could be an unpleasant shower experience. And they have a pretty high amp draw. To me, it makes sense to stick with LP or electric standars tank setup as they are not subject to varying flow rates or ambient water temperature. Great for S&B where flow rate and source temp are constant, I would definitely give more thought to an appication designed for a prescribed flow rate and temp in an variable rate and temp system. But that's just my opinion.