We stayed at the Modern for 4 nights on our way through to Maui, then for 1 night before flying home. Everyone who worked there were friendly and helpful, and made lots of accommodations for our 9 month old daughter. Suki was especially fantastic, but we couldn't fault anybody.
The location was far enough away from the hustle and bustle of downtown Honolulu, but close enough to walk there. The pool area was lovely, and very relaxing. The amenities were modern, clean and stylish. It was a very "cool" hotel, that wasn't even trying. We loved it, and will stay there again.
Our only issue was the noise. On our initial stay, we were near some kind of service corridor, with the customary bumps and bangs that go with it. On our 2nd stay, we could hear/feel the vibration/noise of what I assume was the night club "addiction", but it might have been from across the road or something. A bit of an issue with a 9 month old, but if you're without kids, who cares, right?