I've got one of each, because my old ATV isn't worth enough to part with. I've found I use the ATV around the yard, running out to the end of the place and back quickly, running over to the post office, visiting the neighbor 3 or 4 blocks away, etc. The ATV is quick on and off, easier to jump on and off, when I'm working on the yard.
Longer trips, SXS 50". Much less physical. More relaxing to drive long miles and a lot easier to cover really rough country. Been over nearly every trail with a 50" gate in our area and my opinion is the SXS handles the really rough rocks and nasty stuff safer, easier, and with far less stress than my ATV. I think the extra length on the SXS chassis allows you to bridge the boulders and deep ruts. (That could change, in the years to come, as the SXS begin to erode "their" gaps in the trails.) I'm sure there may be trails that are too steep for the SXS, compared to some high end ATV but I've yet to tackle one that my RZR 570 didn't go right on up, and I'm a pretty hefty load.
I still miss my horses but I gave them up long before I bought my first ATV, so they've put me back in the game I was missing out on, without the horses.
DC