I'm 5'10 and I ride 191s so maybe for you (considering at 5'7" you're 173cms) I would go anywhere upward of a 175 would be fine but if I were you I would be looking around in the 180-185 region
180-185 should be money, i am about those same dimensions... but yes it also depends on the ski, ie my turbos (104 underfoot) are 175 for trees, i wish they were a bit longer, but its a great crud ski, my JJ's are 185 for the float
