I hava also ordered an annularis, and will be placing it to a mixed reef.
The first one that came died soon in my LFS, and now I'm just waiting for the new one to arrive.
If you really want one then get it! It won't eat ALL your corals. When it starts to pick on something then just take the coral out and give it to someone else...
I have 3 large and 4 dwarf angels at the moment, and the only one who has ever picked at anything is my 10" imperator. It ate all zoas, but that I knew will happen.
I sold most of my LPS and zoas before I got her, and I actually think that it would have been wiser to just see what she may eat and then start to pull the corals out...
If my annularis starts to eat some corals then I can live with that. I know the risks, and I'd rather have that fish than one or two corals more...