We have a Sea Recovery Aquamatic here on Charmer, it was installed in the spring before heading north.
great unit, it's fully automatic even the weekly fresh water flushes are automatic so you dont' have to worry about the membranes. It's a 900 gpd model but they a smaller 450 gpd model, identical except for the membranes. No vibrations at all, a slight whine from the high pressure pump but it's in the ER so it can barely be heard. they have to version, all in one or modular if you dont' have the space for the all in one and need to place the components in different areas of the ER
i woudln't go for a DC model on a boat with a genny, it uses too much battery power, you will need to run the genny to recharge anyway. Going too small with an AC model means you will need to run it and the genny for longer period of times as well.
The only issue we've had are with the pre filter. The installer suggested the standard filters woudl be fine and that it wasn't worth trying to fit the larger commercial filters. it's true in areas with clear water, like the bahamas but not along the east coast, particularly up north with plankton. I didnt run in the Ches. but in long island sound and nantucket, we clog the prefilters in a matter of hours. they're easy to swap (change the 25 and 5 mic, and clean the plankton filter) but it's still a pita. I wished i had insisted on the commercial size filter and found the space myself...
Sea recovery makes a media filter which replaces the paper filters, high capacity than the commercial filters and cleans by backflush like a pool filter. Something to seriously consider up north.
That said, a watermaker is still an extra system you need to "worry about", maintain, etc... so unless you really need it, nothing beats larger water tank. but if you cruise the bahamas, or spend a lot of time on a mooring or on the hook, then it's a must have.
