Paul2000, do mean you are not familiar with a diesel water cooled gen made by Honda? Water cooled diesel gens are the standard and commonly available. Gas powered portables are the exception.
I am a complete newbie. I know very little about boats or sailing, but I believe I would like to give it a try. I am a very considerate person in a camp site, and would be so on the water. It is a resource we all share and I would definitely put out a little extra cash and effort to get a quiet generator. If the diesel water cooled generator is the norm on the water, then that is what I would get. I do have knowledge of the Honda 2000 gens on land, and compared to many others it is quiet, but it may not be quiet compared to the diesel gens on the water. Looks like I have a lot more to learn about sailing than working the canvas.