Ken, I think that the Onan is a great generator, for a couple of reasons. The have a full pressure oil system, oil pump and a oil filter. You do not get this with the portable. They also have a fuel pump so again you get a fuel filter, that is if you are using gas. They also for the most part use a slow speed gen-set, and anytime you can run at a slower speed you are much better off. But you also must take into consideration the cost. The Onan 4000 watt RV generator can be bought on the internet for a little less than $2,000. 00. The portables can be had for less than half of that price. Also Ken, it seems that the Honda's portable generators are quite long lived, that used to be a reason to go with generators like the Onan. However with the quality they are building into the Honda, they may no longer be a consideration. Good Luck with whichever you go with. Gunny