I do not have engine bay pics of the hookers yet. The pics in my build thread are the old blackjacks. They fit pretty good but I had to use a bfh to get clearance at the steering shaft. Fitment wise the two sets are very similar except at the steering shaft. The hookers went in without any adjustments. They hug the block closer vs the blackjacks. I do not know what gauge they are both made of but my set of blackjacks are noticeably lighter. Where the pipe is welded to the flange at the head is thinner on the blackjacks. Not much sealing surface. That mounting flange is also thinner. I had a hard time keeping them sealed there. I used regular, double layer steel, then double layer copper gaskets. I always had the header tick. It was better with the copper but still there. I have a ground down 3/8 wrench I carried with me all the time to snug them up.
The hookers sealed fine using the copper double layer gaskets. The only problem I had using them and the double layered gaskets was needing longer header bolts. I have put about 2,000 miles on the hookers and have not needed to re-tighten the header bolts. I had to do it repeatedly on the blackjacks.
The hedmans I have were new. One set still in the box. They came with project II's I picked up along the way. One set is on the Mach I now. The last posts in that build thread covers the problems they presented. I know others have used them with success. Both of my sets are bent wrong out of the box. The are parallel at the flange and collector but should have a mild kick down. As is they are too close to the floor and crossmember. Once the collector flange is on there is not enough room for a pipe to clear the crossmember. That car is a stock 302/4 speed. I could try to bend them downward but then I still have the one pipe going under the front crossmember. It would probably be okay on the Mach I as it sits higher but I would certainly smash it on Christine as she sits lower.