The only real arguement for a WB (IMO) is the fact that it captures your arrow. Supposidly this will help prevent your arrow from falling off the rest during a draw.

With that said, I'd rather push my arrows though air versus a brissle-brush. With the variety of drop-away's on the market, I'm sure you can find one that does what you want. I prefer the simplist, strongest possible designs. I like the Trophy Taker, simple, works, and won't budge once tuned.