if it is well maintained it should be good. (Not sure if you are looking to buy used), I had one recently sold it, and didn't have any major problems, yes, minor stuff (spark plug) but well maintained they are good. I used a special four stroke oil though for years..
https://www.searchforparts.com/utv-oil-change/john-deere-2016-gator-rsx-860i-860.0