Replying to Help with Armada BDOG size

I'm having trouble deciding which length to choose. I'm 5'7 and 156 lb, I stay 90% park and 10% in the trees.
Last 15 years I have been skiing with 178cm skis, always center mounted.. but the Armada BDOG 180cm seems long and 172cm seems too short to me. I consider myself as an "expert" although I don't go too hard, I like chilling. I don't go into big air so maybe I won't need the length.
thoughts or recomendations? thanks