I am constantly entertained by Bloggers who ask these kind of wide open questions. I would hope that one poor soul doesn't make a decision based on what COULD be an armchair snowmobilers uneducated opinion or someone's secretly steroid induced 600 cc, what ever brand it may be, whoopin up on some half witt's 800 cc that has a bad belt and is 500 R's short. There are so many variables when comparing even sled side by side I ride an 09 800 RMK 155. When ever we get with a different group of guys on different brands, I always ask to test their sled. Seat time is the only way to base a true opinion on a sled. I would ride a Cat any day and could switch back n fourth al day long and not miss a beat. I think that if someone gave me an XP, I would learn to love it, but for now, they seem to have a very large upper hand on my ridin habits. I can not form an eduvated opinion on a Yami because I have spent but 10 minutes in a trashed hard pack meadow. The power seemed good, but they all rip on a flat hard surface. The bottom line is turn the computer off and get out and test ride all of what you are interested in. I am very dissapointed that I haven't ran into a 2010 M8. I am anxious to ride one because I am not impressed with the 07-09 M8 motor. I had an 07 with a speedwerx pipe, y and can and was not impressed. I jumped on a demo 09 162 M8 2 weeks ago and, again, was highly dissapointed. Good luck in whatever you decide on from the Half witt Hot Shot...