The Buffet at the Wynn is definitely one of the higher quality buffets in Vegas. The selection isn't as great as other buffets, specifically the seafood (no oysters) and dessert (no macarons) but the quality sure made up for it. The prime rib was perfectly cooked and seasoned and the crab was sweet and not too dry. My favorite veggies (asparagus, brocolini rabe, and wedge salad) were perfectly cooked and prepared. Our family really liked the pasta and Asian offerings as well (Asian food was not greasy).
Our server was not the friendliest, but was prompt on refilling our drinks and clearing our plates.
Vegas buffets sadly have decreased the quality of their buffets, but we're glad the Wynn isn't one of them.