Matted filefish seem to be the 'safer' of the filefish but many will attest to that not being true. Ours does not mess with our corals, but I do not have any 'meaty' LPS coral that seems to be a delectable delight for them.
I tried an orange-tail filefish (Pervagor melanocephalus) in a reef type tank and boy howdy was that a mistake. He ate zoanthids, a fungia, snails, hermit crabs, a clam, and when he went after the cleaner shrimp enough was enough. There are some other corals he killed but for the life of me I can't remember what they were. He did not go after the frogspawn and xenia but I think it was just a matter of time before he did.