Have never been to Boma, but I really like Kona! Ate there twice on our trip two weeks ago. Great seafood chowder and wings.
Also, FYI, the bar at the Poly (next to O'Hana's) has absolutely fabulous lettuce wraps! Sadly, we only discovered them on our last night. Great grilled chicken, shredded carrots and cucumbers, some kind of Asian slaw, and peanut sauce. I practically licked the plate! (Plus, they were only $8!) Big enough for an appetizer or light snack for 2, or a meal for one. Try 'em!