We love ours, we have an old Swan 38 and live in the Northwest US. It
does make a little noise in the back of the boat, not annoying, just
enough to let you know its working. I have it plumbed in with three
outlets, one in the aft cabin, one in the main and the best one in the
head. We don't have pressure water, but the heater makes it much more
comfortable in the winter. I don't do any maintenance, other then
running it every month and changing the filter once a year.