We like 'Ohanas for the food. The atmosphere was okay, nothing to really scream about, and we're all adults, so the kids activities didn't do anything for us. We are there for the first time a couple of weeks ago and loved it. We felt we actualyl got our moneys worth, had a good variety, and the food was all good - except the pork which was too dry (seems to be a common problem! I wonder if anyones complained?)
The sides you begin with are delicious, the breads good, and the meats were yummy. My husband had to have seconds on the pineapple dessert it was so good. Plus your drink is included, too, and everything is all you can stuff.
I don't think it compares to the Luau, you should try it and see for yourself. Some people love the grilled meats, some dont... we love grilled meats at home, so we knew we'd enjoy this. =)