The dead horse of sheet metal quality...

[mike16]

I've searched. I've researched and searched some more.
No clear answer.....yet.
Im window shopping for '72 C10 sheet metal.
So far I've determined that at least two manufacturers of sheet metal exist and sell through numerous vendors. AMD and Key. Are there other manufacturers?
Im just looking at this time but it seems that there is a difference in quality fit and finish. And also newer vs older suggesting an improvement in quality over time.
So my question is the same question that others have asked repeatedly.
Who manufactures the highest quality reproduction sheet metal?
How can I avoid first run crap that vendors might be trying to unload?
I keep hearing that all sheet metal comes from the same source overseas and it does not matter which vendor you buy from, it's all the same. But AMD and Key both claim differently. Are they using a verbal shell game to hide the communal source of all sheet metal from customers?

Im not trying to disparage the manufacturers or vendors. Im going to make a i time purchase of sheet metal, doors, fenders and bed sides and would rather pay more for a better part. Like everybody else, I want to know from somebody with direct experience rather than others with opinions.

Thank you for any help you may offer.