They do float differently, so there is every reason to believe they sound differently when popped. Aged Sage is correct in saying that what we hear doesn't matter. If you get more hits with one than the other, that one sounds better to the fish. I prefer hairbugs, since they definitely sound different. I compare it to (cork or plastic) a 2x4 smacking the water or (hiarbugs) swishing a twiggy branch into the water. I get more action with the swish.
"Give advice when asked. Give praise when appropriate. Give discipline when needed. Give respect always."