Hi,
I kept one for years, they're a very cool fish. However, the may cause a bit of carnage as they get older, the move everything around in order to search for tasty morsels to eat, and this can become a pest if you have delicately placed animals. Like most fish, it probably depends on the individual more than anything else as to whether it is invert safe. I haven't got one in my reef, but I may in the future, I'll see how daring I get. They get to about 11" long but get a juvenile and he shouldn't get that big.
HTH,
Tom