We always have great luck with em! Just I'm skeptic on rays thats all. Cause I remember about in 2000 when they were boomin in popularity they were not doing well in some tanks.
If you meet the proper husbandry requirements for each species and get quality stock free of parasites, they should all live long time!.. some just have harder husbandry requirements, and die easier (eg: retic).. or are treated poorly at distributors.