Nankang suck.
Kumho Ecsta Supra are apparently a AA grip rated tyre, but I hate them so much, I think they are just soft, not a good gripping tyre.
Then I have brigs GIIIs on the rear, they seem ok, they have worn better than the Kumos, and seem to grip ok once they have a bit of heat in them.
However Im not writing off the kumos yet, Im going to adjust the front suspension settings and see how I go from there, but first impressions (about 6-9months now) I dont like them.