I installed a few systems this summer. One for our barn apartment, which I mounted the outdoor unit under a stairway, hung from the stringers. 12k BTU 120v Costco cheap, Super quiet, rubber foot mounted it though. Also our daughters house had a very poorly installed gas furnace/duct system. It was so bad with leaks it would take several thousand to do right. I installed 2 3 ton 3 head mini splits. One at each end of the house with line sets out to the 6 locations. Either system would heat the home, but this is what they wanted. I re-used 2 circuits from prior 240v hot tubs, replacing the proper breakers, lower amp HVAC rated. They love the systems, each room is so well controlled and so quiet. Their home is so much better balanced, the AC was essential for my pregnant daughter this summer, and now the heat is working so well. We recently had temps in the low teens, unusual for Seattle, but all worked so well no need for their gas leaking duct system to kick on. However, I would argue that at a SEER of 22, these mini-splits are far more efficient than a central HP typical SEER of 16.