We have a 6500 Onan. I bought it for the ease of use. We travel with dogs. If we are not in our fiver and the power goes out the auto start feature will kick in at a set temperature. That way the dogs won't cook in the heat. At rest areas turn on the generator with the flip of the switch, run ac use micro. even watch tv if you want. The noise for a 5500 or 6500 is rated the same by Onan. With an LP generator you will need to run it for one hour per month under half load to exercise it, per Onan. We are full timers and the convenience is well worth the cost.