Repro parts are simply put a "nightmare." I have many examples of this from my Boss 302 and 67 GT350.
I have had many many many parts that were bad from a BIG place that when you go to their website, you see that they sell stuff for other brand cars also, even trucks like Toyota.....That to me is a warning sign. Guys who do not wander and stay focused on Mustangs and Shelbys tend to be much better even when a part is defective. (nothing really bad about a Mustang and FORD place, buy TOYOTA, as Lie'n Biden would say, "Come on guy's")
I just do not see the argument that, 6 cyl. guys want to buy cheap parts vs. Shelby guys who "usually" want to buy the "Good" parts. That to me is like saying, I want to set myself up for a breakdown on the highway, or I want everyone to see how cheap I did my car over.
I like my guy who, does his best to "restore" a part or panel that is original. The problem also, these guys are getting old. I hate to see how future "projects' will be restored. Caring how a car is "done over" will be an issue.