I have done both and prefer Hoop Dee Doo. They are both wonderful in my opinion but for different reasons.
What I like about the luau - Very beautifully put together, lovely dancers doing traditional dance, exciting fire show, beautiful music, great food, nice seating set up.
What I don't like about it - Tedious (really just the same thing for a long period of time), some food kind of different if you have picky eaters, monologue or story line is not good - acting by the dancers very poor
What I like about HDD - Exciting, great food (and alochol comes with it I think like beer or wine), Wonderful visual dancers and costumes, great acting and great music.
What I don't like about HDD - Seating is sometimes not the greatest although you can see from anywhere - the front is best of course and they are more $$.