Satisfied with the heat pump
We have used ours down to the point where our water lines froze at the hose bib over two winters now. It is a 13.5K unit; I would have specified 15K, but the trailer was bought off the lot.
I find that our unit keeps the trailer comfortable right down to the point where it switches over to furnace. It switched over briefly on the coldest night that we encountered ... the one where the hose bib froze.
We have no problems with distribution. With the louvers pointed slightly downward, we are comfortable in both ends of the trailer. The bathroom does tend to get cool with the door closed and I turn the furnace on briefly when we shower.
In the 25' trailer, I find that the 13.5K unit is just adequate to handle Texas summers. OTOH, with the 13.5 unit, we can keep the water heater on AC and use the microwave without blowing breakers; probably not feasible with the 15K unit.
The one scary thing about the heat pump was my experience a month ago when mine switched over from AC to heat pump when a thunderstorm played games with the AC power. Once in heat pump mode, it would have run forever had I not been there, spelling sure death for our cats. The problem seems to be that commands from the comfort control thermostat to the AC are coded over a 4-wire telephone cord. Apparently, that night my AC misinterpreted a command due to noise on the lines. I have now isolated the wire that activates the heat pump valve and will install a toggle switch this week to deactivate the heat pump valve in the summertime. This may be something that others with pets might consider doing.
John W. Irwin
2018 Interstate GT, "Sabre-Dog V"