Is there a differance in who makes the engine and how many different h.p ratings are there? I am talking about the ones in the 6k range also. On E-bay some are advertised as 10hp, one as 11 and one says theirs are 13hp. Naturally you want to get the best for your money. One has a two year warranty, one a one year, one no warranty at all. I dont place much faith in the warranty. But would be ok if they just supplied you with the parts, if it went bad (free) during the warranty. As crating the gen. back up and shipping it back would cost you $3 or 4 hundred. One mfg says they supply you with spare filters, parts manual, spare gasket set. I visited my neighbor yesterday, who bought one from Northern tool (not the exclosed one) and he said it was very fuel efficent, about 1/3 of his gas gens. He felt he could roll it around better and more portable than the enclosed ones. His major complaint was very noisey. I personally didnt think it made much more noise than my Coleman. I would not be moving mine around. As I have another gen. if I had to load it in my truck to used it some where else. I have heard that the enclosed ones are quite a bit quiter. The only problem is you have to remove all the sheet metal to work on it. I havent seen one of them. But it lookes like there is a lifting ring in the top center, and I could just put a chain through it and pick it up with my loader if needed. I still havent made up my mind as I have run onto a Onan, around 6K. and I think it is a 2 cyl and operates on only somewhere around 1500 rpm. which would make it pretty quite and smooth. It has only about 60 hrs on it. It is propane. Most people say I shouldnt have any trouble in getting propane. I've got to go back and look at it when I get a chance. I dont think propane would be quite as easy to get in a long range emergency as diesel.