if you are just trying to do like 3's and 1's and rails and stuff, find a stiffer older ski, i recommend chronics and ar5's from the past few years. if you can find the 04/05 chrons, get them because they are a great ski for what you want to do in and out of the park.
i say a stiffer ski because they are(i think, some people disagree) more forgiving on landings, because you don't have to land right on your feet, you have some leeway(sp?). I say an older ski because you can get them cheaper, and you probably won't notice the minute technological advancements of last year to this year, or the year before even, if you are just getting into park.