We've been to O'Hana's 3 times. Once was meh, once was FANTASTIC, and the last time (Sat during Gay Days) was good. It seems to depend on where you sit, what time of day (if at night, do you have a good view of the lit up castle and/or fireworks, and your server. Our server in December (when we went for my birthday) was awesome, and the chef visited our table to make sure I liked my birthday cake (which was also awesome). Last time (June) the food was good, service was pretty good, and seating was good.
We ate at WCC last year for Aidan's birthday, and it was just okay. We all agreed after we left that it wasn't good enough to go back.
We LOVE Boma though, and that's where we usually wind up. I'm a big fan of all you can eat.

(No FAT jokes people!)
ETA: I typed the request for no fat jokes prior to the comment by Rosie. I know you too well.