It is well worth the money. It was such a great experience when I went. The you are seated starting at 5:45. It is an indoor area, so weather and heat or cold is not of concern. A band comes and plays from 6:00-6:20ish and then the actual show starts at 6:30. The show goes until between 7:45 and 8:00. The food was terrific, the show is awesome. I highly recommend it.
Here is some more info on the menu. And a short video of some clips from the luau.