I must have the 'old' Borla headers 1 5/8", because they don't look anything like that. Those 'new' ones look even better. The Borla headers I got from Sean Roe were for a Gen II and I had to grind a notch in each flange to clear the head bolts on my GenI.
I like my Borla headers and make good power with them.
798rwhp 1042rwtq w/ nitrous
480rwhp 505rwtq on motor