I'm looking at buying this model, 3400 miles on the chasis but the seller states that he just did a top end rebuild (cylinders and pistons), has 300 miles, because one cylinder seized because of bad gas. From what I'm reading this might be a crank problem. What do you all think? Also, I currently ride a a Thundercat MC, the cat is heavy and 136" track, but I love the horses. Stick with the cat or try this Polaris, or ? Any other sled reccomendations?