I have a two unit Daiken mini split in one of my rentals. A larger unit in the living room, and a smaller one in the master bedroom. They installed the whole thing in one day. The tenants love it. Very quiet heating and cooling. Very efficient as well. One drawback is the other two bedroom doors need to be open to receive the benefit of it. In Oregon, there was a state tax credit for it. I don't see why it couldn't work well in an RV if it was well secured. It would certainly be much more quiet than the stock furnace that blows more noise than heat.