I stayed in Waikiki Marriott for two months during my business projects and it was an amazing experience. Although it is located at the end of Waikiki, the walk is not that far from the heart of the attractions; it's about 10 minute walk. The room is very small, however, the quality of the bed is extremely comfortable. They already renovated all of their rooms and quality wise, it's beyond expectations.
Their service is great, the people are very friendly, and during my two months stay, I basically hang out with the Marriott associates. They are very nice and definitely they have the "Spirit to Serve".