As long as they aren't the only fish in the tank or first in, these guys are great in community tanks. Just that people misunderstand the rules as seen from a Damsel's eyes: I'm here first, ergo tank IS mine. Fish here, I'm new in the neighborhood, need to make friends."
My yellow-tail was an utter pacifist before the heater malfunction. Often picked on. They ARE NOT mean little beasts at all, unless of course, you buy a Blue Devil damsel. Different scenario then! LOL
Matthew