I like cat whiskers for several reasons. They don't hold moisture, scent, or burrs. They work better than anything I've tried--SVL has made a fortune (literally) from silencing products made from rubber.
Two big mistakes I see with cat whiskers: One, people leave them way too long. Too long can produce it's own noice. Two, they aren't installed properly. They should be tied on around the string, so they can be tuned. Moving the silencer up or down the string just an inch or so can make a big difference with some bows. The silencers have a "sweet spot" just like the brace height--you tune them for the best results.
Properly installed and tuned, it normally only takes a small set for great results.
Chad