Here we go again. This post has been empty for a while. Everyone must be tired of answering the same question. Based on rider feedback and being out and about with the two brands I have this to say. Cat has been more reliable. I am a POO rider, but I honestly think that the XP is probably the most efficient out-of-the-box sled of the big 4. When I say efficient, I mean it goes through the pow the best and seems to go the highest on the hill. They leave very little track where my POO leaves a trench. Are they the best handling? To me NO. I would have to spend a week on one to feel comfortable. Do they handle great on the bumpy trail while Cat sucks it up, YES. Does Cat have a desirable powerband? to me NO. They feel almost like a 4 banger. If I had to pick between the 2 and ride it stock and never open the hood except for oil, I would choose the DOO. If had $2500.00 to spend after I got the sled, I would choose the M8 hands down. I just spoke to one of SLP's techy's today. He said that the 09 M8 with the Perf Package is still the most fun sled to ride that he has ridden in a long time. There you go. If you decide on Cat, I just talked to Mountain Magic Sports in Preston, ID today. They have some good deals on some left over 09's. By the way, my comparisons are based on 09 Cat and DOO. I have NOT PERSONALLY witnessed a new M8 yet. I would love to ride one so I have an educated opinion on the sled. Good luck with your choice