I have an AMD front bumper on my Cuda. I bought one of the last ones available about 2 years ago. I bought it from Classic Industries with a discount code and got a really good deal on it. When I received it I opened the box and checked it out and it looked good from an eyeballing it point of view. I then closed up the box and put it in the attic where it sat for about a year.
After a year I finally got the car to the body shop and a couple of weeks later I brought them the bumper so they could do a test fit. We opened up the box and the bumper on one end was all distorted. We mocked it up on the car and it was a mess, I was literally sick to my stomach at that point. The thoughts that were going thru my head were.... great, I'm now out $600+ on this bumper and I will have to use a chrome bumper on an original rubber bumper car. What made it worse was one of the body guys was like I'm not sure we are going to be able to use the bumper. I left the shop depressed.
After about a week I went back down to the shop to check out the progress and the car was sitting there with the front end all on including the rubber bumper and it looked awesome, even in all primer. The body guys said it took them many hours to get the front clip adjusted and to work the bumper over to get it to fit properly but they got it.
So from my experience I would say these bumpers do have some issues but can be used. I still don't understand what happened to the bumper (why/how it got distorted) from the time I closed the box when I first got it to the time I opened it up a year later. The bumper was not stored at an angle that would not have caused the distortion that happened. Now that I read this post I wonder if this is what you heard.
Anyway as mentioned above the story has a happy ending and the bumper is on the car and looks good. I have attached a picture so you can see how it turned out. I apologize for the angle (doesn't do the car justice) but it is the best picture I could get in the cramped garage.