What sled are you coming off of????? That is what is going to determine if you will have an issue with a new sled. Years ago I rode a 809 skidoo Mach Z. I quit riding for a few winters, and came back on a skidoo 1000. I loved it compared to the Mach Z. Last year I sold it and bought an 09 xp. Unreal!!!! It has all the updates, C3 forward steering post, S36 front end, 2010 rear skid geometry (longer shock, scissor bracket etc). It is a blast to ride. About 2 weeks ago I rode a friend's 2013 xm, and it was fun. I didn't think it was a huge improvement over the xp, but it sure was easier to hold a side hill. Every time I got a new sled, I became a better rider, and was trying things I probably would not have with the sled before.
Now that I have told you about my upgraded 09 and how fun and easy it is to ride, I don't think you need all that to have fun. My 13 year old Son has a totally stock 08 xp with 4000 miles. He rode an 05 skidoo 550 fan cooled for one year. Now he has rode his 08 for 2 years, and I can't believe how well he rides it. He can do steep down hill turns and come back uphill, he can sidehill through the trees all day long. When he gets on my sled (09), he can work the tight stuff a little easier, but for the most part he can take that 08 anywhere he can take the 09. The xp chassis is just a great sled, and all the little upgrades from 08 to 2012 just seam to clean up small details from the year before. So depending on what sled you are coming off of, you can't go wrong with either one of them. This is just my opinion.