I have a Yammy 3000se. I've found it will run 12-16 hours with "eco-throttle" (Honda's term) flipped on. Hard to get better, although I've lusted after a set of red twin 2000i models for the ability to run an extended run tank, and the fact they are easy on the back.
The only hitch I've had with it is having to flip off the low RPM throttle switch before using the A/C or microwave because otherwise it might not be able to spin up enough RPMs to handle the starting loads. (I don't have the "boost" model, so if it gets too much of a starting impulse, it will go into overload mode.)
As for noise, my RV is in a camp with a number of people. None of which had any issues about the noise, and most of them didn't even know it was running. To me, the fact that -nobody-, not even the really noise sensitive ones, notice the thing make the generator well worth its asking price. Supposedly, it is quieter than the 2000 watt models, but since 2000 watt gennies can be positioned better for sound deadening, it probably balances out.
Maintaining it is pretty easy. Just make sure you can get a thin pan underneath for an oil change.
Would I buy one again? Of course. It can both recoil start as well as electric start, is good enough to get some juice in a dead battery that smart chargers won't touch, runs my A/C, converter, and microwave without issue, and will happily run all night long.