going sled skiing with my friends in a group. (riding up and skiing down)
well for what you want somthing with good suspension and motor. If you have the funds just buy new or slightly used.
But if you don't have self relighnt way to up-keep a sled, (have somone in your group who is snow machine-savy) your going to be paying alot for repaires.
You need constent money for for a High peformence snowmobile (which is what you need for they type of riding your going to be doing).
If you have alot of extra money (+ $10,000) and want a snowmoblie buy a decent one and prepair to spend extra service and parts. go for it. otherwise skining is the way to got.