there's a reason boats have been painted usually they have repairs so you may strip part of it but you will find the repairs and then have to repaint to hull anyway. Also the more you buff the less Gelcoat you have and that's thin to start with so you only get a couple buffings before you will have major problems with osmedic blisters all over the boat cause the thin gelcoat will take in water and the glass under that will create an acid and eat holes in your boat. go with this
http://www.poliglowproducts.com/index2.phtml