Well I by no means am BangGuy but I think this may be a sufficient answer to your question...
It was once thought that bristleworms were bad for a tank, eating up livestock. Now its understood that they are actually benificial detritus eaters and scavengers. They got the bad rep because people found them all over livestock that was sick or dying. They got the blame but they were, in fact, just eating the dead tissue. I actually have one of those traps. They work quite well. Unfortunately, I found out that they were good after I removed a large number of them. Now I have very few.
Anyhow, dont bother with the trap unless you have infesting amounts of them. They are good critters.