I hate listening to a Honda running in an otherwise quiet harbor! As quiet as they are they are really annoying. I own one that I use with our Airstream (sparingly), it is a 3000 W model that is as quiet a generator as is made. It is also not run on the water, we all know what happens to sound on the water....
The biggest offenders seem to be the 1000 and 2000 watt models. People who own them will quickly say how quiet they are and how they only run them at appropriate times but I hear them running all night long all the time. They may be quiet from the perspective of the owner but not from my boat.

I prefer the idea of solar panels or even some of the new wind powered generators. There is an industry that seems to be cleaning up its noise signature in the past few years.