We use plain old Raccoons in our 8 or so SPS-only propagation tanks. Have also used false-falculas (C. ulietensis) in a couple mixed reefs with great success, minimal/no picking. I also have had Copperbands behave as model citizens in mixed reefs, as well. As always with this topic, some people will say otherwise, and everyone has an opinion. General consensus seems to be Pyramids, but I've never personally tried one, and they are a little more uncommon in the trade (at least with our vendors).