I installed the heater in Alameda, CA but had very little chance to use it before leaving for Kona last summer. It produced a lot of heat and can't see needing anything more powerful for my 35' boat even in below freezing conditions. Probably won't turn it on again till summer after next when I sail up to the PNW. I talked with a number of owners about their experience with the heaters, however. All reported clean burning and few problems with them. Biggest complaint was backdrafting when a pressure differential develops between cabin and the deck in gusty conditions and/or sailing. That sends a cloud of black soot into the boat. Dickenson has a fan that forces gases up the flue and prevents a backdraft but it's really to get the stove started and warmed up, not for constant use. The solution that seems to work, for everybody that tried it, is a separate flue pipe mounted next to the burner and running up throught the deck. That keeps the pressures inside and outside the boat balanced and virtually ends the back draft problem. It means two complete flue systems, one for exhaust and the other for balancing but seems to cure the backdraft problem.