I had a trip to Sydney a few weeks ago so had dinner with Mrs_G at Quay. It's been written up enough on this Board and I'm with previous visitors - it's superb. I would say it is the best restaurant in Australia at the moment. Great combinations, stunning plating and flawless execution. Standout dishes were the confit pig jowl, a mackerel sashimi salad, and a ewes milk ice cream (and the ubiquitous snow egg). Almost all dishes were excellent. Mrs_G had some switchouts as she doesn't eat shellfish, and her carrot dish was outstanding - always a good test of a restaurant.
That said, it is breathtakingly expensive - the location is probably one of the prime pieces of real estate in Sydney. The premium wine pairings were good pairings, and a couple of standouts, but probably a bit too expensive for the wines they served. I'm not sure if I'd do that again.
It was great for a blowout meal, and service was world class. I was impressed by their sincere treatment of a couple of girls on the next table on a cash-constrained special birthday treat.
You pay a lot for the view - I probably wouldn't rush back, sinply because paying for a view doesn't do a lot for me. But if I wasn't paying, or had a special Sydney occasion, I'd be back in a flash.