The difference between Neil Perry's original Rosetta in Melbourne and the newly opened Rosetta in Sydney is, essentially, the difference between Melbourne and Sydney dining.

Rosetta Melbourne is a moody, theatrical, draped and chandeliered space with a rich, meaty menu; while Rosetta Sydney is all light, sunny and seafoody. 

Melbourne is damask cloths and crystal chandeliers, roast pork and Tuscan bistecca, while Sydney is three cantilevered levels in the Seidler-designed Grosvenor Place, complete with outdoor terrace, mezzanine bar and a menu of scampi crudo with blood orange, mint and pistachio; tagliolini with spanner crab; and whole grilled baby snapper with salmoriglio. 

The seafood acts as bait for the loud power-broking lunchers and a more mixed crowd in the evening, happily hoeing in to hand-rolled grissini (points for that), house-baked focaccia and generous bowls of fruity olive oil.

Designer Melissa Collison has kept the chairs velvety and comfortable, the tone sophisticated, urban and business-luxe, and the themes marble, bronze and ribbed wood.

I go hook, line and sinker for a seafood antipasto of raw and cooked scampi, crab, squid, prawns and mussels ($39) that's light, fresh and sweet. There's good salumi ($28), and pizzette ($16). Zuppa di pesce ($45) is celebratory, with lightly cooked mussels, octopus, clams, prawns, cuttlefish and fish lolling about in dark juices, with garlicky grilled fingers of bruschetta for dipping and dunking.

Head chef Richard Purdue cooks with a light hand, happy to give tradition a tweak or two. His gnocchi ($29) is a warm bath of beautifully balanced oxtail ragu coating light, potatoey dumplings, with cheese grated at the table (points for that, too).

Veal also features – not just any veal, but Cowra milk-fed Torello rose veal from the otherwise unwanted male calves bred from dairy cows. It's dark and beefy rather than pale and milky, giving gumption to vitello tonnato, rock salt-grilled veal rump, and a freshly crumbed veal cotoletta on the bone ($49) that's as big as your face.

As at London's acclaimed River Cafe (which I suspect figures as a muse for Mr Perry), most mains are what-you-see-is-what-you-get, necessitating side orders of, say, slow-cooked cavolo nero, chard, rapa and tomato ($14).

Rosetta is about wine as much as it is food, but you pay for the privilege. There are no bargains on the vast, distinguished, Italian-led list, with an intense yet delicate 2014 Bertani Valpolicella Ripasso from the Veneto ($21/$95) and a clean, subtle 2016 St Michael-Eppan Schulthauser pinot bianco from Trentino Alto Adige ($21/$95) sitting somewhere in the middle.

Cute little cannoli can be had for $5, or a rich slab of torta di Verona for $21; all whipped mascarpone, pandoro sponge, marsala, blueberries and crisp flaked almonds – although mine needs a little more time for the cheese to ripen and bloom.

Senior Rockpool hands keep up the pace, and the kitchen is closing in on the early-days gaps. But this is an impressive offering. At just a few weeks old, Rosetta Sydney has the bearing of a restaurant destined to be a vital part of the high-end dining landscape – proving that Melbourne and Sydney aren't that different after all.

The lowdown

Best bit: Snaring a prized circular booth on the kitchen level

Worst bit: Loos are a (slow) elevator ride away

Go-to dish: Zuppa di pesce, garlic bruschetta, $45

Terry Durack is chief restaurant critic for The Sydney Morning Herald and senior reviewer for the Good Food Guide. This rating is based on the Good Food Guide scoring system