Farmed at Big Glory Bay, Stewart Island, for the past six seasons, the oysters until now have only been available on the island, but were on the menu at several upmarket Auckland restaurants yesterday.
Auckland-based chef Simon Gault, who has secured North Island distribution rights for the oyster, said "the reaction has been absolutely fantastic".
"People are saying they are the best they have ever tasted."
Despite a price tag of $6 each, the oysters were being snapped up by patrons who couldn't wait for the March 1 opening of the Bluff oyster season, he said.
"Bluff oysters are still fantastic, but personally I think these are better than the 'Bluffies'."
Oyster farmer Alister Eade, of Stewart Island, said there had been "tears and tribulations" in trialling the certified organic oysters, which he named Southern Glory three years ago.
"It has been hard but worthwhile, but we think we are on to something."
Not wanting to compete with the Bluff oyster, the Southern Glory may be exported during the regular oyster season, March to August, but this was still several years away, he said.
The same variety of flat oyster, the Southern Glory was bigger, sweeter and creamier than its Bluff counterparts, he said.
But the variety would not be as readily available, with supplies limited to several North Island and Stewart Island restaurants, Mr Eade said.
Farmed in part of a 13ha marine farm at Big Glory Bay, the oysters, apart from a two-month spawning period, were able to be harvested year-round, he said.
Fellow oyster farmer Jim Maass-Barrett, of Stewart Island, said he had been selling them directly to locals and visitors from his Kai Kart caravan for $12.50 per 125gm.
Like their Bluff cousins, the farmed oysters were better eaten raw or battered.
"They taste brilliant - people love them."
Mr Maass-Barrett had taken out patents on how to commercially farm the oyster.
"After trial and error, we have discovered how to produce and harvest the oysters and are now starting to reap the rewards."
Graeme Wright, manager of Barnes Oyster in Invercargill, said the new product was unlikely to harm sales of the 7.5 million of Bluff oysters harvested each season.
"We are pretty relaxed about their presence."
Mr Wright rejected claims from Mr Gault the Southern Glory oyster was harvested from a cleaner, deeper area than the Bluff oyster.
"Our ones are taken from a deep part of Foveaux Strait and are dredged from a gravel bed - not a muddy one as he says."
Likening the farming of oysters to that of battery hens, Mr Wright said people preferred their oysters growing naturally.
