Many of the pay atv parks have a class 1 limitation which is 50". That is why the RZR is classified as a class 1 at 50" and allowed to run in these areas, all other UTV's are class 2 or class 3.
As for width I have the diamond J Customs +6 widening kit on mine as I could not find any a-arms for a 1st gen. So that is like having +3 a-arms. I also have different offset wheels to push the tires out a bit further. It handles great and is not any wider than my friends Raptor 660. Remember Warriors are pretty narrow to begin with. It would be different putting +3 a-arms on a YFZ 450 or even a Raptor 660 or 700, That would make the quad much wider.