Really depends on your price range. I've heard that Sanderson and Thorley headers are pretty top notch. But they cost more than the Hedman or Hookers. Unless you want the top of the line Hedmans or Hookers. I personally think that you cant go wrong with a set of ceramic coated (inside and out) Hookers or Hedmans. You might try and find one with a thicker flange, as the thin ones tend to warp easier. But you can always cut the flange to remedy that. As far as my personal experience, I had a set of Hookers that the flange warped on my 350. The Hedmans I ran never warped. Didnt notice any performance difference between the two.
There are quite a few header manufacturers you can check out...Edelbrock, Sanderson, Hooker, Hedman, Flowtech, Gibson, JBA, Dynomax...