Chains youll get varied opinions on. O-ring and X-ring chains offer the best protection against breakage, on the flip side, they need to be cleaned and greased more.
Non-Oring chains need to be replaced more often, but its said you suffere less HP loss through the chain, which to me can be important on a little quad that doesnt make a lot of HP to start with.
Im running an O-Ring chain I got off Ebay. Has a high tensile strength and has been a good chain. However next time I replace it Im going with a non O-ring chain because Ive ridden 2 dirt bikes back to back, both were RM250s with the same mods/work done, one had an O-ring chain, one a non O-ring chain and the one with the non O-ring chain was quicker by a bit.
So, I dunno. To me even a non O-ring chain should last a good season or 2, and with how cheap chains are, I dont feel 50-60 bucks every other season is a lot to pay to keep a good chain on there.
Its all about personal preference.