I've had both and they both have their places. I miss my old buggy and am building another now but it is nice to have the rzr to ride for a backup rig.
With that being said in January me and my dad finished up a single seater rzr 900. It is by far the most fun and capable thing I have ever driven for what it is. I've never had a buggy with stickies or a giant motor to compare it to but for just a little rzr it is a blast to drive and climbs better than any other rzr that we've ever rode with. It climbed tub rock this weekend and I know my old rig never would have done that. And it will fit on a small trailer and is easy to get wherever you're going. I don't know if you could compare it to what most people call a built sxs or not but considering when we started with the rzr we had every part for the build already that made it alot easier to do. Only picture i have of it at the moment.