ZukkinMad,
I purchased the Calmini 16 valve header. I have no complaints. It was a direct replacement for the stock exhaust manifold, everything fit perfectly. This header included the tube for the EGR cross-over port, along with the threaded collar for the upstream O2 sensor. I have aproximately 30,000 miles on this header and it still looks very nice.
I have had no experience with the Hawk header, so I can offer no opinions concerning it.
I realize this thread is rather old and you have probably made a decision and acted on it. Just putting in my two cents worth for those that may read this thread.
Sincerely,
Nine Pine