These generators are fairly simple in concept. I think the Onan's are well made and mine has been an extremely good generator. I haven't got a clue how many hours it has on it and I really don't care. The gauge said 144 hours when I bought it and it still says 144 hours. I suspect it's closer to 1000 than 100. When we drive to the beach in the heat of the summer we run the generator and the roof AC all the way there and all the way home.
Both the generator and the AC unit are 23 years old and both work great. In fact, I have a brand new Dometic 13500 BTU AC on my wife's grooming van and it's not even close to the old AC unit on the RV in it's ability to cool even a much smaller space.
