Forget those buffets! Have the steak or prime rib special at Ellis Island on Koval Lane behind the Paris Hotel/Casino. You won't find it on the menu, but you just got to point to it on the menu cover. I still think it's one of the better meals for the price in Las Vegas - about $12 and that includes a tall glass of their great home-made beer. Or a Root-Beer if your under age.
But if you still want a buffet, go off the Strip to Henderson to a Sushi Buffet that Onlyme can identify and tell you about.
I've been in every Oriental part of the world and have to admit that the sushi at this place is the best I've ever eaten and each piece looks like a work of art. And if you are "prejudicial" against sushi, they have loads of other American type foods on that Buffet line.
And at the end, scope out the chocolate waterfall!