Rammer, I have had both. Last year, I had a Polaris 800 EPS LE. It was decked out. I used it to plow snow. I really liked the Polaris a lot. I have a John Deere tractor, and have had several of them. When it comes to farm equipment I am a John Deere guy. I decided, because I mostly work my UTV and use it less for recreation (though still wanted something sporty) to go back to JD with the 825i and sell my Ranger. I have the Powertach blade on mine, but would have gotten the Boss Power V had I not gotten a great deal and some built-in upgrades to the Power Tach that made it too good to pass up. I have not owned but have had experience with the Kubota RTV in this setting as my neighbor has one. There is simply no comparison between the Ranger and the Gator for plowing or any type of heavy work. The Gator plows snow much better. It is heavier, has more power in the mid-range and more usable torque. With equivalent tires it is the far better snow removal machine. And this information is coming from someone who has used essentially the latest renditions of both machines (not comparing a 2003 Ranger, for example, to a new Gator or vice versa). My neighbor really likes his Kubota and I would rate it to be also better than the Ranger for plowing snow. The only two issues the Kubota has is that it does not have a good power to weight ratio and thus does not handle our steep hills very well under load (i.e., it is much slower than my Gator) and it is not true four wheel drive. Therefore, when really slick and steep it can get stuck.
The Ranger has some nice qualities the Gator does not though. I preferred the operator station and seat on the Ranger, and I also preferred the brakes and the fact it had factory power steering. I added a Unisteer kit to my Gator, which is as good or better than the factory Polaris system and can deal with the cabin shortcomings to have the heavier construction, better powerplant, and better company backing and warranty. As I noted earlier, there simply is no comparison in this arena. It is true there are other offerings out there such as the Bobcat, etc., for UTV plowing but I do not suspect any of them are better than the new Gator or RTV Kubota. The Yamaha Rhino is a great off-roading side by side but a virtual toy in this setting. Like the Ranger it lacks the sprung weight to move a lot of snow (not to say it cannot do fine in many cases, though). One area of concern to bear in mind on the Gator is fuel usage. The 3 cylinder gas engine in the 825 is thirsty, especially under a load and I felt the Ranger did get marginally better economy when pushing but I could not push as much snow or push it as fast or access the same areas with it either, so it likely is a wash there. My vote: 825i with Boss Power V and Sno-Pro spreader (be sure to get the Bighorn tires if you can). If economy is important to you and you do not have steep hills consider the 855d or the RTV, though they are both also expensive and not nearly as fast in transport.
John M