Ski length/bdogs

figured I'd make a thread to get a few more opinions... looking at armada bdogs 176 or 181, I'm about 5'8" and 176 armadas from past years are just slightly taller than me. will be using them almost entirely for park, more rails than jumps. I'm around 150-155lbs... how much taller than you do you guys usually like skis with mellow rocker? Armadas measure long compared to most, I've ridden regular camber 176 armada skis (thalls) but thinking I could probably get away with 176 in the bdog with the increased width, rocker doesn't seem terribly aggressive either...