I have had a 2008 500, 2009 850, and currently have a 2013 550. All of them have had expensive issues with the ADC, that Polaris did not honor, yet it is CLEARLY a design issue. It doesn't matter how much or how little it is used, it is going to grind. Best advice is at every service change the ADC fluid, run it around the block, then change it again. I will not be buying another Polaris with the ADC in the future. Can-Am and Arctic Cat is starting to look good to me.