I really can't decide what my favorite buffet is, Bellagio or Wynn. I think Bellagio's food is a little bit better but Wynn has the upper hand in the decor department.
This being said, I am growing tired of buffets. It is a casual and cheap dining experience which can be good if I did too much shopping or gambling and my wallet is in pain. But aside from that, there are so many amazing restaurants to try - if I am not feeling broke I don't think I will return to a buffet unless a friend drags me.
However, Bellagio buffet is the best food I have found at any buffet I have ever had in my life. So if you are going to buffet, I would say this is the place to do so.
The roast chicken, German potato salad, and fresh made sushi were the highlights for me on this last trip.