I've been to all three, although Chef Mickey's was for breakfast.
Boma - didn't like the food at all, although many people rave about it. Everything had some kind of sweet taste or sauce to it and I don't eat sweet dinner foods (only desserts).
Ohana - good, but our service was poor. Our "cousin" didn't bring us any food during the Wishes fireworks, even though we had requested more beef and shrimp. By the time the fireworks were over, we didn't really want any more food.