The 600HO is great engine. The GSX is a great sled. I just did a fuel milage calculation for my 2 sleds as accurately as possible. I have an '06 MXZ 600HO that gets 15 MP U.S. Gal. My wife's '04 MXZ gets slightly less but it's hardly a pig on gas. They do have their issues though but nothing serious enough to say avoid them. No crank, overheating, or major break down issues of any kind for 10,000kms combined now. Plus, they're carbed sleds so you don't need a dealer to diagnose an electrical issue...or a battery. My opinion anyway.