If you keep all your Filter pads and Prefilter sponges clean on a weekly basis, it eliminates most problems all the BioBall Haters point out all the time.
If the balls are getting a bit grungy, pull out about a quarter of them, swish them around in a container of tank water to dislodge debris, and put them back in. Repeat every week or two until all are clean. Viola, clean Bio Balls.
IMHO Live Rock in a WetDry will collect far more detritus, and be much more difficult to clean than any plastic Bio ball.