I'm looking to buy an 800 sled soon and have been going back and forth between the Doo and the Polaris. How reliable is the axys 800 H.O? How long will they last if I take care of it? Is their a year better than others? What years got updates? I see the 18s had the MY18 update which addressed the crank problems. Does that mean anything older than 18 will have crank problems?