We have spent a great deal of time on Maui, with much more planned in the coming years. We love both OLL and Feast at Lele (run by the same great folks), and I agree that there really aren't any discounts. OLL is a superb show, gorgeous beachfront, sunset location and has a reputation of being the most authentic Hawaiian luau in the state of Hawaii.
If you've never done a luau and can swing the price, I heartily recommend you go. Happy planning!