I'm an NC30-35'er with dark brown hair. I've used MAC's Brun eyeshadow, but now I use Shiseido's powder brow set. While Brun worked for me for a long time and I did like the depth of the color, the Shiseido brow powder was much softer/natural looking.
Oh, and the good thing about the Shiseido set is that it comes with two shades, one lighter shade and one darker shade. So you don't have to buy a new shadow if you change your haircolor, just use the lighter/darker one accordingly or mix the two to get the right shade.