We have had excellent service from our 2005 1121 a little smaller and lighter that the 1161. It was the largest unit we could carry on a SRW truck, the US Park Service at Assateague Island, Maryland does not allow dually's on the beaches, yet.
These units all require periodic maintenance, particularly on the roof and side seams, and around the marker lights etc. Those who fail to keep up with it pay dearly! Look for bumps and raised bulges, swollen spots which may indicate water intrusion. As well as brown or discolored stains around the ceilings and interior walls. It is not unreasonable to have it surveyed by an experienced technician, it could save a bundle!
We have the Onan 2500 propane generator, it has been excellent. It is imperative to exercise it at least monthly, running it with a load for around an hour. A used gen with low hours should be avoided, they wear worse with little use. I expect a price in the $3500.00 range installed. The Onan is a little more compact than the Generac which has an engine and separate inverter. Both should be able to run the air conditioner. We have found our generator to be VERY helpful and convenient.
We also have struts from the front of the camper to in front of the windshield, that reduce porpoising on certain roads, Lance recommends them and carries the fittings for various models of pickups.
