I'm starting up my 75G tank now. It's starting off FOWLR
, but I do intend on making it a reef eventually. I too was really interested in Flame Angels, but after all my research, my recommendation would be not to get one.
If you read enough testimonials, you see that there seems to be an emerging consensus. There certainly are people who have kept Flame Angels in a reef for an extended length of time without issue. However, there are many more accounts of people who were able to keep one for a while, 1 year, 2 years, and then the Flame Angels suddenly develop a taste for coral, and in some testimonials, they can massacre a tank in a matter of days. The same goes for any other Dwarf Angel, unfortunately.
That said, I would certainly encourage you to get some firsthand stories of people who have kept Flame Angels. I can't speak from experience, so I could only share what I've read online.