I made it past 3,000 miles on my 2011 on the original pistons. Took it apart last week to freshen it up, and everything looked really good. Even though I never turned up the oil pump, there was plenty of oil in the case and a little puddle under each connecting rod. Both pistons and both cylinders looked good. Took it all to my local dealer so that a "trained" tech could give me his opinion. He didn't believe me when I told him my mileage. Was really impressed. Made me feel a whole lot better about the reliability of this motor.
On a side note, the exhaust valves were filthy. I have only used the polaris oil since I heard stories about people having to fight to get warranty issues resolved due to using aftermarket oil. Your power problems could be a function of having dirty valves as well. They are simple to remove and clean and are worth the time.
I am no mechanic, but was able to get everything apart and back together without much more than some bloody knuckles. Anyone with a little common sense should be able to do so as well. Two-strokes are a lot easier to work on than 4-strokes. The hardest part, in my mind, is dealing with the tight confines of the frame. If all you need to do is the valves, shouldn't be much trouble at all. PM me, or ask any of the fellas on this forum if you need more assistance.
Good luck!!