I'm 5'7" 170 and ski on Head Monsters. I think they are like 174? I used to teach skiing and ski everywhere, reeeaaallly fast with a bunch of old CU racers. just like Davis said,rockers reduce your edge contact. I'm a carver and dig trenches, I want edges. :-)
My GS race stock skis are 184. now those are fun at 55MPH.