I voted for Boma. We have been there for both breakfast and dinner, and it is my families favorite buffet at WDW. Why? The location and atmosphere, the unique and tasty food offerings (including wonderful African wines you can purchase by the glass), and the smells (aahh!) The place can get a little hectic (translated: loud) though, so if you are looking for a quiet place, this is not it.
My second favorite buffet is not on your list, so I will mention it here. We really enjoy Fresh at the Dolphin. This place has only been around since last fall, and they just serve breakfast and lunch. We have yet to try it for lunch, but for breakfast it is a top notch venue. There are stations set up (i.e., carving station, juicing station, omelette's to orders, pancakes to order, etc). Because of how this place is set up, everything really is "fresh", as the name implies. The interior of this restaurant is cheery, and we received good service there too.