I used Waeco and it did good job. Except it cycled in a wild and confusing way understandable only to a German engineer
. It used more energy than by the book, but we were in hot climate which probably explains most of the wild difference.
It was a 45 liter (or thereabouts) unit.
I would buy one for my own boat
They seem a bit pricey for what they actually are. Maybe there is some other make that sells the same thing for less money