We have the 4K micro quiet in our 1990 bounder. Its under the table and to me is quiet, but not needed. Luckily when we had our 5th wheel we bought 2 of the EU2000I units and take these along also. I like the idea of solar and summer plans are to add some solar to the camper. I do have a 3K RV inverter also to install just trying to determine location of the battery bank.
We run the hondas most of the time and don't even know they are on.
One think I found with my Onon was the exaust flange was loose and exaust was leaking. Once that was fixed with the venturi tube its not that bad.