My DD was 10 on our trip last summer, and she absolutely loved it. We all really enjoyed it. I had seen some not so stellar reviews and knew it would be cheesy, but I had wanted to see it since I was a kid. We did not get there at opening, and really wished we had so we would have had some more time there. We stopped at the Dole Planation on the way there, and if we had it to do again, we would have skipped the Dole Plantation to get more time at the PCC. We did not get to see all of the shows.
We did the Ambassador luau package that included the Luau, show (HA) , and a guided small group tour. I would recommend that package. You were free to leave the tour and explore on your own if you did not want to stay with the tour. I thought we would probably do that as we are typically more explore on our own types, but we found that we really enjoyed the tour. The guide will teach you about the cultures, do activities with you, and take you to the shows and canoe pageant. Without the guide you would not have a group to do some of the games and activities which DD really enjoyed. We also learned a lot about the cultures represented from the guide. We thought the little shows were very entertaining. The guide knew which ones were the best since we could not do them all, and took us right up to good seats- he also got us to the canoe pageant on time to be on the front row benches.
We really enjoyed the Luau. The luau ends before it is time to enter the theatre for HA, so after the luau, you had your choice of a few different activities. DD is a theatre kid, so she chose a backstage tour of HA. She enjoyed it as she got to see the cast warming up and getting ready, the costume room, props etc.
We stayed for HA and we did really enjoy it. We got very good seats with the Ambassador luau package We felt like 90 minutes was just a little too long, especially after already attending the luau, but it is definitely worth seeing and the fire dance was fantastic.
The drive back to Aulani was fine. It is an easy drive and we did not run into any traffic after the show.
I think your boys are just the right age for it. If they enjoy learning about other cultures at all, I think they would probably enjoy it.