There have been a couple threads recently on these in the tech area. They're the 87 units but same basic design other than the location of the outlet. Do a search and look at some of the feedback.
They are literally the non-turbo headers that they adapted for turbo use. That's why there's tons of extra plumbing and that's what slows the spool so badly. They may make more top end power, I could not tell, but a Honda will out 60' you every time with these.