We recently stayed at the Beach Tower on 2 occasions (en route to and from Canada).
As a family of 6, our choices in Waikiki were limited if we wanted an apartment close to the beach, so we are SO thankful that the Beach Tower exists!
I do not need to elaborate much, as most of the prior reviews are accurate - the views (from the higher floors at least) are the most amazing I have ever experienced in many trips to Waikiki, and the location ideal. Being just across from the beach it was so easy to come and go as we pleased, our teens could head up to the room while we stayed on the beach with the younger ones, and you could even watch your older kids surfing from our balcony!
On our first stay our apartment was very well equipped (our second stay not as good, less kitchen equipment, pans not big enough for a large family etc) but on both occasions the beds were very comfortable, the apartments were quiet and we were exceptionally happy with our stay.
A suggested improvement - There is a large frosted glass partition next to the front door of every apartment - overnight it lets a LOT of light in from the outside hall lights which made sleeping for those on the sofa-bed difficult - resulting in us having to stack a tower 7 foot high of sofa cushions next to the glass to block the light out!)
But next trip to Oahu, we already know where we will be staying :-)