Beaver balls work great on bows you don't need much silencing on in the first place, and they're much nicer looking than catwhiskers. But for a bow that has more twang than beaver balls can handle, catwhiskers are about as good as it gets. Work just as well as those fancy-schmancy gizmos, last a LOT longer (if youtie them on with serving instead of knotting them around the string)and cost a heckuva lot less.

If you have a really loud bow, try and find a set of the old wool puffs. Best thing ever made for silencing, but they do slow your arrow down a good bit more than the others.