Ok... I've searched through a few forums and found a lot of opinions... But I'd love to hear them all in one place...
I'm going to buy a Tundra for this winter. 154 track. But, what engine to choose? It'll be primarily an access sled for ski touring. Minimal towing requirements, not looking to charge hard ($$). I've sledded quite a lot for work (mostly 600 and 800 summits, and some awful Yamaha 4 strokes). I'm 140lbs. Needs to be a good reliable machine for Yukon winters - I'm kinda horrified at the concept of no pull start, but I think that's the Yamaha paranoia shining through.
My gut says 600 ACE - fuel economy, reliable motor, I like to cover some terrain without hauling a bunch of gas.
My pocket says 550f - $2k cheaper than the ACE, have to go through a lot of oil and gas to balance that out. But, seems the least reliable of the bunch. But has a pull start (is it an obsession?? should I worry??)
My dealer says - Xtreme with 600 ETEC (has one for $1500 off). Brings the price to where the ACE is.