Buffet food is designed to be served at all hours. A pan of something sitting out in a steam tray will tend to get dry. MDR serves you the food as it is plated in the galley, so it will probably be fresher looking. That said, there is no telling what will turn up at the buffet. The soup from the MDR one night might repeat at the buffet the next, and so forth. I did once see lobster tails on the buffet, but that was years ago and they were dinky, dried up things. The only thing you can't wear in the buffet is a swimsuit.