I love my flame. It's never picked at my zoas(and I have a lot of them) Occasionally it picks at pocillopora but I really don't care for that particular coral so it doesn't bother me.
every now and then mine will pick at something, but I think he's either mistaken or picking at something I can't see. Other than that *knock on wood* he's been a model citizen.
Make sure you feed them their proper diet. Hikari now has that mega marine angel formula with larger mysis and a mixture of everything else they eat disguised as small worms, so there's no pickiness like I observed with Formula 2. I supplement that with Hikari mysis in a 1:1 ratio,