I bought 2 new Ski Doos last year, mine is the GSX SE 600 E-tec 2 stroke diect injection. The other is the Grand Touring LE with the 900 Ace 4 stroke. Since I started using Startron fuel treatment a few years ago I have never had any problems in any of my small engine toys, tools or equipment.
With the 2 stroke you push a few buttons on the dash and the engine fogs itself and they really don't want you to run it again until the next season. With the 4 stroke I change the oil at the end of the season and make sure the fuel has been treated and run through the injection system and wait for the snow to fly again. The 2 stroke calls for 91 octane while the 4 stroke can use 87 with no problems.
Supposed to be getting colder and chances of sleet/ice/snow in Wisconsin to start then more snow hopefully, I'd take snow over ice anytime too!