I would have to say power wise all the 440's are ABOUT the same. I favor Doo (of course) mainly do the "seating position" or rider forward design. The rev chassis just amazes me in the bumps. My second choice would be the Polaris. Never ridden one but it looks good and has the rider forward design.
Cat would be the absolute last, I am done riding the "kitchen table" design sleds, Cat says rider forward but I just don't like it