This is a hole in the wall joint owned by a Vietnamese/Chinese family. Overall authentic and pretty tasty.
It's located in the Kino'Ole strip mall. There is no sign on the outside. We found it only because our friends who live on the island took us there. It's for locals in the know and was pretty packed. I think we were the only tourists!
It's a bit more expensive than the pho places that we're used to in LA but then again, everything cost more on the island.