Not a lot of info around about this fish, so i'm glad someones posted about it.
I have been fortunate enough to keep most of my dream fish, from my wish list. And this fish was at the top of my list, and always will be.
I have had mine for about 2 years now. It is the 2nd specimen i bought. This fish is definitely not reef safe at all. So only for a FO. Small specimens are more difficult to adjust, while medium and large fish are easier (same as the Golden/Addis B/F). Once they start eating everything including flakes, pellets, nori etc. they are very strong and not as fragile as they look. They eat loads and appreciate heavy regular feeding.
I have had the same experience with both of my fish, keeping my first 1 for about a year. It was the first marine fish a ever purchased. It would eat every bit of coral I ever put in the tank, so it turned me into a FO keeper. It died in a tank wipeout from bacterial infection. ( at that time I did not have the knowledge of identifying disease and treating with correct medicine)
The c. Rainfordi I currently have is exactly the same in behaviour to the first. This one was medium size at purchase. It lives in a busy tank with 3 other butterfly fish, 2 tangs and a lot of medium to large angelfish. It never gets disease, when others did. It is a perfect fish for a FO tank with Angels and Butterfly fish.