I'm converting my 180 to SPS and have been researching large angels and SPS. I've spoken to many people and more than a few experts and four species seem to keep coming up as pretty safe bets, they are the emperor, blueface, Red Sea regal, and the navarchus. I think there are some other pretty safe bets as well especially in the Apolemichthys and Chaetodontoplus genus. I really wanted a meridithi but they are pretty rare and there doesn't seem to be very much info on them. I am leaning towards the majestic or blueface myself.