I have a guy that I work with and his son is the head mechanic at a Polaris dealer, he has been a mechanic on Polaris sleds for 11 years now. After reading the thread and buying a 2013 800 motor I had some concerns as I am sure you can tell by reading my threads.
Anyway my friends son said Polaris started having problems in 2009 with the 800 motors trying to meet EPA standards, he said they basically leaned it out to much. Since 2009 they have different pistons, heads, and have remapped the fuel. He said things improved every year and in 2013 they did not have any blown motor's come back to the dealer he works for. However I do not know how many sleds with 800 motors they sold.
I figured I would post this information hoping it will help someone. I agree all brands have their issue's, however we all have different personalities and opinion's which makes for great threads and disccusion