Replying to Does the length of my ski matter that much?

Im kind of new to skiing (started half way through last season) and dont really know much about the small details of the gear.
I've run into a little bit of an issue.
So, my friend is willing to trade his 166 afterbangs and some bindings for my old snowboard. He's buying new skis and wants to try snowboarding too. Perfect right?
But i also found a pair of 184 Step ups, from last year, brand new (in plastic) for 200 shipped on NS.
I'm a little strapped for cash because i need to buy a season pass still.
So would i be ok with 166's, or would the 184's make a big difference?
I'm 6'3" 210 lbs. by the way.
K+ for any thing constructive.