Replying to '11 Armada AR7 Sizing help

Hey, This will be my first ski purchase in like 10 years....

I go 75% park and 25% All Mountain, decided on the AR7s, seem to get good reviews around here

I'm 5'9'' 165, and formerly have been skiing on 165s (non twins) and was wondering since i'll be center mounting, should I go up to 171?