I do have to disagree somwhat about what people have said about brakes on a 4x4.
First of all, both of these machines are 2/4wd, so seperate braking would be a real advantage.
Second of all, even on a full time 4wd such as a Wolverine, it is not the same thing as having linked brakes.
If I'm coming down a very steep sand hill and I put on the front brakes hard, the front wheels will lock up and dig in. If I put on the back brakes, the front wheels won't freewheel, but they won't dig in as much either.
For low speed riding on flat ground linked brakes might be very convenient, but one of the first things I would do if I bought a Polaris or an Arctic Cat would be to split the brakes.