It looks like a Tubastrea, but I have never heard them go by the name orange cup coral. Google "Tubastrea" and see if that is it. If it is then they are fairly difficult, and need feeding 2-4+ times a week.
i have a very large piece in my tank. i wouldnt say that its difficult to keep, but yes they do need to be fed about every 2-3 days. i feed mine frozen mysis and chopped up krill.
I have had one for quit some time now and they need moderate to low lighting and it is one of my favorite corals. It never really came out until i got the right food for it in my tank. when they actually come out they are beautiful... My fish store that i use gave me some special food for it nd now it comes out alotmore than it ued to.the food he gave me for it is cyclop-eeze. Id suggest that if anyone has a sun coral do some research on that stuff. Like i said i had mine for almost a year and didnt come out to much till i found the right food for it...
orange cup coral is just another name. Yes I have one, I feed it mini mysis shrimp. It is known to be a difficult coral because it is a high mantainence coral. As long as you feed it, I think it is not too difficult to keep.