The Step-Ups will be the most durable and have the longest length option. The Suspects will probably the lightest, and the Antidogmas will probably be the softest. I'd say go with the Step-Up out of those 3. I have had the Antidogmas, and they were fun, but unfortunately they don't last long (but longer than the Suspects would have). I wont even touch the Suspects until they prove themselves more durable (or someone is willing to give them to me and constantly replace them). I had the Afterbangs last season, and the only thing I wished about them was that they were stiffer - which the Step-Up is (I also wish they were a bit faster, and I don't know if they fixed that).
FYI: Suspects might be the best performing park ski ever. But they break super fast and they are heavy. My S4s weigh over a half pound less than pairs of suspects (it's 4.25lbs 176 Suspects vs 3.65lbs 174 S4s per ski) and they last more than 10 times longer per pair (that's not an exaggeration). Just so you know. I love riding suspects but I will never own another pair. S4s are the most bomber ski ever produced period though, so not a fair comparison.