IMO & IME; all anthias are on the difficult side. I think lyretails are one of the easier species, along with bartletts and dispars. Pink Squares are quite difficult; they are deepwater fish and much bigger than most anthias. They are very difficult to acclimate and will lose a lot of their brilliant colors in bright light. I've kept a lot of anthias and am convinced that they do better in pairs or trios---or even 1 male with several females.
The hardiest fish I ever owned was a female lyretail that lived through a tank crash and a poisoning. She lived 8 years.
You really have to have a nice size tank to keep a trio and it's even more so recommended to keep a harem over a trio. I have 3 different species of anthias. Two kept as a single specimen and one is a trio.