agreed, both will excel in park or all-mountain, but the agent has more lean toward the latter while the postermania enjoys the former more.
really depends on your thing. if you like riding the mountain and really just take laps through the park on the way down, i'd take the agent. a board with a heavy freestyle slant kind of sucks when riding through variable mountain terrain (with exceptions). you'll have more overall fun with this.
if you're the type to spend an entire day at the park, unstrapping and walking back up, etc. i'd take the postermania.