IMO it really depends on what you want to use it for. The Rhino is more of a pleasure riding machime to go fast with. The Mule is a slower workman type utility vehicle.
I have the Kawasaki Mule, and I really like it. We also have a Polaris Ranger, and it is also a nice vehicle, but I prefer the Mule. The main reason I like the Mule is that the Polaris is all plastic, And the Mule is basically all metal. Especially in the floor boards, and bed. The Kawasaki is not as fast, but I am not in any hurry.
I also prefer the bench seat on the Mule, I do not like the bucket seats on the other two. And if you are a large person then the Rhino is very cramped.
There are a lot of differences between the 3 bikes, so if I were you I would write down all the uses you will be using it for, then pick the bike that best fits your needs.
IMO the Mule is considerably more rugged for heavier use, but not as fast for pleasure riding. However if you ride on Sunday with your friends, you will be the favorite person on the ride, because you will be hauling all their stuff. Tom.