Snowboard questions!?

ok so basically i need to buy a snowboard, i skateboard a lot so this isnt something im going to be doing a LOT, i just wanna do it for the winter season, so basically i was on craigslist and i found a really good deal on a snowboard with bindings (avalanche board which is apparently not a very good choice, and rage bindings) i am around 5'7-5'8 and the board is 155cm, i want to do mainly park so like freestyle type of stuff, is this board worth getting? or too big? i have snowboarded before multiple times, so i would consider myself intermediate.