Doug, Mini-split has a single condenser and compressor and feeds freon into 1 to 4 registers that make cold air directly. No cold air ducts. Separate units inside for each room or area. Separate thermostats.
Mostly designed for homes where you can say just cool the upstairs bedroom at night or the office during the day. Large homes would have several units. Big improvement over a central system on one thermostat.
Bit of overkill for an RV. But if many RVs are like mine leaking BTU into the roof cavity the mini-split would definitely keep all the BTU in the living space.
This discussion probably deserves its own thread.