Visited all three last trip (all for dinner). Would visit all three again without doubt but Boma was our favourite.
WCC - skillet - plain, filling and well cooked. Nothing special think eat-in at KFC.
Ohanas - great view of the MK - pleasant entertainment - food quite plain with a twist. Some meats ok others dry.
Boma - souless restaurant but FANTASTIC food.
4 of us - 2 adults and 2 kids (9 and 5) - all four preferred Boma and as we are only returning for a week next time this will be the only one we will try and get ADRs for.
IMHO whichever you pick you won't be disappointed.