I am bullish on the Bellagio buffet - particularly the weekend dinner one. I've also eaten the Rio and the Aladdin (buffets), and in my mind, Bellagio wins. Reasons:
- Best seafood. Most buffets have crab legs and prawns in Vegas. Bellagio goes over the top with (selection varies) smoked salmon, sushi, sturgeon, sea bass, a seafood gumbo with scallops and mussels etc...
- Best roasts. On the weekend buffets they have exotic roasts I've seen - genuine Kobe beef, venison, game hens, quail, bison, a superb beef wellington in addition to the staples of turkey, ham, roast beast etc...
- Some of the best desserts. I'd say Rio is better for those with a sweet tooth. But the Bellagio desserts do kick ass. Also a nice sugar-free section for those who prefer.
If you starve all day and brace yourself, it is EASY to get your moneys worth. If a decadent dinner buffet is part of your Vegas experience - then I'd say Bellagio wins. Just have a wheelbarrow ready to trundle you back to your room or the Roman vomitorium at Ceasars Palace.
BTW - I've heard that the Wynn buffet is fairly mediocre, given the opulence of the property. Haven't tried it personally tho.