If you want a turbo, 4 stroke is the only way to go for a true pull and go sled. I had a 09 dragon 800 with a aerocharger 66, when it ran good it was great, but I spent alot of my day playing with that stupid fuel box. I now have a 12 M800 and a 12' M1100 turbo. The power is impressive, my dragon was 240HP, the 1100 is 177HP out of the box, mine has a lightweight silencer and it feels just as strong if not stronger than my dragon did. Smooth power all the way, and literally turn the key and ride.
That being said, knock on wood, but my M800 had 900 miles on the original belt, did the updates and threw a new belt on it just because and it now has 1500 miles and still no issues. My M1100 had 500 miles on the original belt and still looks great. There's a big differnece in the way the two feel, I can throw my 800 around good, but not so much the 1100, but I'm only 185Lbs. Going to see how light I can get that 1100 down to, but a guy can drop 50Lbs off of it between hood, seat, battery, silencer, reverse delete, ect. With that combo I think it will be kick ***, and reliable. Also 8" skis and a 38" front end will really help out.
Good luck to you, you won't be disappointed. There are good proclimb sleds out there, I have 2!
-Kyle