I attended the RZR Camp event In Berlin NH this weekend and took the opportunity to examine and test drive a RZR 1000 S to compare it as best I could to my Z800.
The good: Polaris did an excellent job of laying this machine out has laid for easy access and maintenance. (The Z8 is archaic by comparison in this regard). The driveline of the RZR is both potent and responsive and the suspension well balanced and forgiving. It was a nice ride even in the bumps.
The bad: The machine was skitchy and unpredictable under even moderate acceleration on the trails. It would literally twist about and move off the centerline (and off the trail) instead of accelerating straight ahead. I can only assume that this is a characteristic of their On-Demand AWD system. It certainly made for an "exciting" experience, but this is behavior I would not want in my machine. Engine braking was almost non-existant so I had to make liberal use of the brake pedal during the test.
The dash consists of a small analog speedometer that is difficult to read (small print), especially when bouncing along a trail, and I didn't see any other instrumentation of any kind. Its fair to say that this machine is sparse in content.
By comparison, the Z800 has a very easy to read digital dash panel with lots of lighted indicators, selectable information display, and a wider variety of switches. In addition, it has a hand brake that I find invaluable, a roof, a winch, a horn, mirrors, EPS, and most importantly - excellent engine braking for better and safer control of the vehicle on the trail.
The price comparison of the discounted 50" RZR ($15,300) and the Z800 Trail just didn't make sense to me at almost 50% difference. A 50" was not available for test rides, so I can't make a direct comparison between the two on ride and performance.
I can't justify the cost of a RZR for my riding requirements but I can see why the RZR would be the prefered choice when power is the deciding factor.