I have run ITP sand stars on a 10 inch wheel, and they are NOT a good choice if you want to give yourself the best chance at beating your cousin. 21 inch, 8 paddle haulers on a 8 inch wheel would be a great choice, spend the extra money and get the "bead to bead buff" if you can. Proper choice of paddle can be the difference between winning and losing, if everything else is close. Sell those to your cousin for a good price, he will think you are doing him a favor, then, when you smoke him, shrug your shoulders and grin.