I'd stay away from the newer 550 XP types if you do a lot of stop/start work like moving cattle or sheep. My '09 550 has done two "clutch" units ( and a power steering unit) with only 860 hrs!! I'm told by the dealer their seeing increasing "clutch" failures , they lock up and your stuck in whatever range and can only stop by turning them off. Apparently the new style is inherently faulty, I did a couple on my previous 500 Sportsman at around 800 hrs each and none on my previous 4 Polaris quads. Time to change brands for me, if you wheren't doing the stop/start a lot these are lovely, comfortable and very capable quads.
Hugh
Hugh