be honest with yourself.  if you're a pimp, go 181.  if you're not go 176.  if you have any doubts of going 181, go 176.  they are a bit shorter but you're in that middle range between both skis.  i'm 5 10, 160 and i rocked 176's for  a bit and they were mad fun, but at the end of the day i would have gone bigger