We recently stayed at the Adina Darling Harbour and it was one of the best accommodation experiences we've had. It was my wife's birthday and on arrival we were told our original booking had been upgraded to their top studio room over-looking the harbour. We were also given a bottle of wine, which was an amazing gesture. The staff were super friendly and pleasant to deal with.
The room was modern, well equiped and well set out. Of course the view of the harbour was awesome and the sound proofing was very good at blocking out the nightclub noise from the street below. It had a nice and dark bedroom and the hotel was quiet all round.
From Adina, you can walk down to the King St Wharf and Cockle Bay Wharf bars and restaurants, so it is very handy for a night out. Only a short walk to the nearby train stations and they offer parking (which we didn't need).
I'd definitely recommend the Adina Darling Harbour to anyone wanting a clean, quiet and handy place to stay in Sydney.More