I would shy away from the Wildcat X 4 seater. It is under powered and they have lots of issues. Most have motors that leak oil, cracked starter and a list of other stuff. This what I have seen from my friends that have Wildcats. Most of them have moved on to new machines. The wildcat 4 seater does ride really nice, but the issues that come with it are not worth the headaches.
If you can swing a 2017 or 2018 4 seat turbo XP that would be the way to go. There are huge rebates on the 2017 models and the pricing the 2018 model is really good. Otherwise a 4 seat XP1000 does great in the dunes.