I've had two different individuals the first for over 2 years and the one I have now for about 1 1/2 years. It's in my avatar. The first was perfect lived in harmony with LSP. zoas, SPS clams everything. Lost it in a bout with ick.
The latest one was fine until a rabbit fish I introduced showed every one in the tank just how yumy zoas were, now the heniocus and even my fox face devour all zoas they see ... instantly.
Still, it is safe with my SPS and calm and even some LPS such as trumpets, froggy, hammer, and even a few favia. Both mine remianed faily smal through the first year and a half but really begin growing after that. They do get quite large!