I installed two of them about 5 years ago: a 16.5K BTU unit and a 12K BTU unit. They have been flawless, both in cooling
in summer and heating
in winter. I chose them partly because of the electric
instead of the usual reverse cycle marine
types (so, no moving parts
except the fan), because of the quality of their build and the accessories which Flagship ships with them, and because both the USCG and the Canadian CG use them.
Very happy with them so far.