I've got one and he use to nip at corals more than he does now. As a matter of fact he loved Pocillipora so much that I'd buy them just to let him have something to eat instead of my other corals. But no, he even stopped eating them. He's constantly swimming around the tank and is what I call my "terrorist"

He really likes to harass my McCosker's wrasse more than an other fish in the tank. I just got a Yellow Candy Hog Fish last week and they're best friends. Like I said he does harass the other fish but not in a bad kind of way. Some of my fish he completely leaves alone. I think if I had put him in last he wouldn't be doing the harassing that he does.
For the most part he leaves all of my coral alone now, that he's gotten passed eating the pocillopora and he's not nipping on any of my acans or Euphyllia's. I've got a few mushrooms and a couple of leathers and he leaves them completely alone. My tank is mostly acans and Euphyllia and I've got 3 BTA's, he leaves them alone now. So he only was nipping at different corals I guess to see what they taste like since Cherubs are grazers. From all that I've read and heard from others that have or currently own them they all say pretty much the same thing. It's rare to get one that is a coral eater.