?? Quality bearings, lightweight?
Going to build up a NOS Viner.

Price, quality and looks taken together my answer is Stronglight A9. If money is out of the equation, get a Chris King.

+1 on the A9. Lightest threaded headset available & beautifully made.

1" threaded?

Danny

As stated for cost no object Chris King, they last forever and the silver is nicely C&V
friendly (especially if you can snag one sans logo).
I'll put Edco competition out there too, very nice piece of work and I always
thought it an upgrade over campy.
while we're at it, the classic campy NR and SR headsets are serious workhorses,
with a bit of yearly maintenance they last forever.

marty

Another vote for Stronglight A-9.

i think chris king deserves an extra point or two for being one of the greenest metal shops around (for example he invented a system to recycle the shavings and oil for machining which is usually very polluting and just thrown out... the way we do where i work)

A9 also wins in the weight category

especially the composite version...

You should ask him what he does and do it...

A lot of chem labs are switching to 'green' chemistry to be more environmentally and user friendly. We use hydrogen peroxide as a catalyst for some reactions which previously used nitric acid which releases nitric oxides. Yuck!!!

Another vote for the Stronglight. I am running the Delta version, which is pretty cool if you can find it.

Again a +1 for the all-metal Stronglight A-9, but a minus1 for the version with plastic cups, hated those. A clean, repacked Campy NR or SR would be hard to fault for a "correct" Viner build-up (you didn't say what year NOS Viner it is), but if you have to buy a new HS, I've been pretty happy with the bang-for-buck of some of the Tange models. And as for "lightweight", I've never been too concerned about shaving grams from this component: I favor smoothness and serviceability, a little sealing in the bottom race is a good thing too. The best deal I found on the Stronglight is from the big French mail-order house xxcycle.com.

I have an A-9 waiting to go on the Casati, and before that I ran a Super Record. The SR was a little pitted, and I managed to crack the crown race (long story). I've used the cheap-o Tange headsets in the past with no problems. Plus, at $10 a pop you can afford to let it get pitted and not stress replacement.

I've never been real obsessive over headsets. I've run the range from Campy SR to Tange to Stronglight to Nashbar and, if properly installed, they all seem to do the same thing equally well. YMMV.

Regarding King: I can see, though I haven't, spending that kind of coin on hubs or maybe even a BB (don't think he makes them but I'd be interested) but not on a headset. Again YMMV.

I'd think a Campy or the Stronglight would be the leading contenders for the OP. As of not too long ago Campy was still selling a 1" Chorus threaded set. Are they still?