I just finished a 4 day stay at the HHV. The last time I was there was a year ago. On this occasion I walked over to the Embassy Suites and the Kuhio. I must say that I much prefer the whole feel and setting of the HHV over the other properties. It's right on the beach and the grounds are beautiful!
On my recent visit we found the service to be good and the food decent. Sure, it's expensive but this is a resort. The Diamond/Gold breakfast was just fine for us. Fresh juice, fruit, breads and hard boiled eggs--in a secluded setting overlooking the lagoon.
I'll take the HHV over the other Honolulu Hilton properties any time. (Though in all fairness I did not visit the Doubletree...so who knows how that one is.)