I use Slicks also. They are the most accurate when you spin test them and remove all the wobble you can. You do this by spinning the washer, and amazingly it works. If you take a b-head off and re-install, you need to recheck the wobble. If you don't have an arrow spinner, you can make one cheap by epoxying 2 marbles side by side on each end of a chunk of 2x4.