Unrelated to the question but related to the issue, why buy two Yamaha's if you already have an onboard generator? I used to own one Honda 2000 watt model that I carried on board. It would charge the batteries and run everything that I needed to run except the AC's. So I would use the Honda most of the time and on the rare occasion when I needed the AC's and didn't have hookups, then that is what the bigger generator was for.
Now if I had a trailer without a generator then yes, I'd get the two Hondas or the two Yamahas any day over one bigger generator.