We had an Attitude with a Generac (SP?) 4000w generator for years. When we purchased our Raptor with the Onan I was amazed how much quieter the more powerful generator was! Ours is also up front under the master bed and while we rarely need the AC we use it regularly for bedtime movies for the kids, the microwave, the coffee pot, etc. When I start it I need everybody absolutely silent or I need to open the trailer door just to hear it well enough to ensure I'm not holding the starter button too long. When running I cannot hear it over the other appliances or my kids talking. The AC itself is definitely louder than the generator. I never worry about opening the compartment door, but I guess that's personal preference.
Of course my ears have had years of abuse and are far from overly sensitive, but my wife hears everything (hahaha) and she does not complain about it at all.