I've had a tuxedo urchin in my setup since the last time I upgraded my cleanup crew. It's a diligent worker and admittedly since the last upgrade I've had no sing of algae. As to whether I can attribute this to the urchin I don't honestly know. One thing I find fascinating is their tendency to pick up items as protection. It can be a bit disruptive but it's always fun to see what was next. Mine actually tried to attach my acans to it, actually unglued the frag from the rock but I think it was too heavy to work. It has attached some zoas and they are doing just fine. When I fist saw this I looked and sure enough there was a chunk missing from the colony. Fascinating.
