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?