The Rio is off the Strip but that is not deterring people from going to it!
Carnival World buffet was the first stop in the Buffet of Buffets for us. I'd say skip the king crab legs. For the amount of work to get that little piece of meat is not worth it and the 'tools' they give you to use are worthless. The ribs were good. The desserts especially the cheesecake and chocolate mousse, were excellent.
Our plates were promptly removed and iced teas and Diet Cokes were promptly and often refilled.