RC,
I did the same checking out of utility vehicles last fall. I drove both gators (4x2 and 6x4), the Polaris and the Kawasaki Mule.
My JD dealer disqualified the Gators as I need to go into water that is 2" to 6" deep. He stated that the open drive belt design of the gator would lead to it slipping after a water crossing. I have bought over $20,000 of eqiupment from him in the past 5 years, so I do trust him.
The Polaris 4x4 and 6x6 are the fastest utilities made today, if you like that. It doesn't mean much to me as the trails are so rough, I can't go fast any way. I didn't like the fit and finish on the demo units I drove, nor the lack of storage. They are also the loudest machines I tested, I didn't like that. While it's real hard to tell from demo rides, I think that the polaris's are the best traction machines and have the best suspension.
I finally bought the Kawasaki Mule 3010 4x4. For my uses, it was the best of the bunch. It is very quiet, easy to have a conversation while toodling along a forest trail. It has good traction with selectable 4x4 and locking rear diff with front limited slip. Tires get mudded up pretty quick, so I will eventually upgrade. The standard front bumper is tough and heavy. ( I had to take it off to install the wench in the provided integral space.) I use it to haul a 5x10 trailer 2 miles into the woods. Max trailer loads have been as high as 3000 pounds with no problems noticed. I didn't know it was that much until I ran it across the scale....
I did demo the Koyker Raptor 4000H. It was and is my first choice. It has 2x the ground clearance, 4 wheel independent hydraulic drive (no differential to hang up) and has more payload and tow capacity than the above units (if memory serves). BUT, it turned out to be a noisy noisy loud machine! It uses an air cooled 25 horse twin that is set to a constant RPM and you vary speed with the peddle. It would be in my garage now, if they used a quiet liquid cooled engine. If that is not a concern of your's then you may want to investigate them.
Raptor and Mule vendor This site has lots of information on Raptor as weel as the kawasaki mule and a few others.
The Cub was not available until after I bought the Mule. It looks good on paper and the Honda engine is undoubtedly excellent, but I have no direct exposure to it.
Have fun!
John Bud