I wouldn't be worried about a 625i at all. Of all the gators coming into the shop the ones I see the least are the 625i and 825. I have seen them with high hours from guys that chase cattle with them every day, they look like they have gone to hell and back and run great.
So far I have yet to see a 625i need an engine replacement/rebuild in our shop, and we sell a LOT of gators. Maybe jdturf has had another experience with them.
Plus, I think they are the best sounding gator!