I have received some excellent panels from Jim Carter, Classic Parts, and a few others.
I have also received a few duds from each of them.

If you want to get analytical, indicate each specific parts by the vendors' names for each part.
Maybe members will remember the good parts and bad parts they have gotten from different vendors.

Here are some lists:
Jim Carter Truck Parts
Classic Parts
Chev of the 40s
Classic Industries
Dynacorn

It would be nice to know the manufacturer(s) of those vendors' parts.