I really agree with you!!!  I think 20 is waaay too young.  I really discourage patients under 40 unless they have real lines to treat.  If someone is getting real frown lines in the center of the forehead (glabella) at 35, then I think it's fine to begin with a little.  But so often it's more anxiety about a wrinkles that might occur.  My point is ...... what if they don't occur??  Not everyone gets the same lines and wrinkles.  You will have spent all that money and time for nothing.   Dr. I