Don't know about NZ whites but I've had some Australian rieslings and
semillons of of considerable age.
Hunter Valley semillons (dry) back to the 1950s have come up well. I once
had a 1934 Yalumba riesling that still had a little fruit in it - along with
expected oxidation.
I've no hesitation in recommending Clare Valley rieslings for longish
(10 -20 yrs) storage. Australian and NZ sauvignon blancs are I reckon a
drink now proposition across the board.
As a one-off the Tahbilk Marsanne - of which I've had a few decades old
offerings - age wonderfully.
French: Back in the early '80s I had a bottle of the '45 Moulin Touchais -
hardly any sign of age that I could see in colour or taste - one of the best
whites I have ever had.
Haven't seen it in Australia for years - where do they sell it?
Cheers!

Martin

www.thewineblog.net
"James Silverton" > wrote in message
...
> There is a rather intemperate argument going on rec.food.cooking about
> aging white wine for 12 or more years. I admit I drink mine long before
> such a date but what white wines, excluding some Sauternes, Tokays and
> Chateau d'Yquem, would be worth saving that long? Are there any
> Australian or New Zealand wines that would be worth ageing?
>
> --
> Jim Silverton
> Potomac, Maryland