Someone talk me out of this (choco. chip star vs. mushrooms)

[Delphinus]

I'm happy to trade away mushrooms, but "caveat emptor" .. be aware that they can potentially grow into plaque proportions. Some people have had them under control for the most part, for some reason they multiply and spread like fungus for me though. This is only one particular type, I have about 4 or 5 different types of mushrooms and only this one type has ever proved to be a headache.

But anyhow. Consider it a standing offer that anyone who wants mushrooms need do no more than come over and harvest some, or trade me an equivalent rock, or whatever. Basically I don't want to suffer a net loss on the rock, i.e., if a rock leaves the tank I'd like to replace it with a similar sized one.

But my post was mostly me just fantasizing about a way to justify keeping a certain starfish notorious for not being very reef friendly, and seeing if there was still a reason to not try one even in this specialized scenario. Any thoughts on that one?