I sailed 18 months with one of their 60l/min units.
It was very reliable, and as the OP says produces more water per Amp hour than any others I know. I had it running of the 12V service bank, with individual switches for the pumps so I could run it at half speed if I wanted to.
It has some kind of energy recovery unit that goes "thump" every five seconds or so, so I wouldn't necessarily call it silent, but then I don't have much reference, maybe other brands are noisier!
It doesn't like bubbles in the incoming seawater, but recovers production quickly as soon as it gets bubble free water.
The only quirk it has is that if you are unlucky when you turn it off, the thing going "thump" will stop in a bad position and refuse to restart. In this case you need to press a mechanical lever on the machine. Mine was mounted in a way that this lever was very hard to get at, which was a bad mistake
It produced superb water and never had any trouble or malfunction for 18 months. This was 4 years ago. I just saw their new units last week at METS, and the only thing that had changed was the color. I belive this points to a solid design.