Polaris has been around the longest with the RZR, so the amount of upgrade parts and support is the best out of the group even if the vehicle may not be the best when OEM outfitted. They have a good range of products but choosing which one is the best for you can be overwhelming for a first time owner. Some dealerships will try to push stock on hand rather than the best fitting model which does not help.
Yamaha has taken a chance with its manual shifting YXZ. I know two owners that went from buggies to the Yamaha because they did not want a CVT. The negatives for the Yamaha are poor slow speed capabilities due to gearing and a soft frame that easily bends. There are aftermarket upgrades that help, but this machine was designed for open space more than technical riding.
Can-Am is not popular in my area for UTV's, so I don't have any guidance or reflection on their models.
Arctic Cat gets a lot of grief in my area as the vehicle that always has to be towed back to camp. I'm not sure if it is a bias in the groups I know or if there is some data to support this. They recently redesigned the cage because it was a known safety issue on that machine.
I drive cheap China built vehicles. They are not as capable or durable, but the value for the dollar is there even with the occasional failures. Expect to be your own service center and order all your parts online if you choose one of these. If you enjoy wrenching on your equipment they are easy to work on but it's not one of those machines where you drop it off at the dealer and it comes back working. Mine are are still going after 9 years of use, so they will last if you take care of them.
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