Unless you go on a serious mission and document the fasteners on non-restored originals, how are you going to know what fasteners are correct anyway?
AMK are pretty good from my experience.. I haven't restored a concours car, but what I have been supplied by them to replace my old rusty OE stuff, -theirs is practically indentical in most/all cases. Also, I did learn that they are supplied by many the OEMs that made the fasteners in the first place.
Many OE part numbers are simply not available and they won't simply default to an incorrect substitute. That will be up to you do if you want to.
Maybe your not finding convincing results because you're relying on uploaded pics on their website.
I have noticed that they will upload a pic of a particular bolt in one finish only, that covers several different finishes of that bolt and part numbers.
For example. B-12586 and B-12587 are exactly the same bolt in S2 and S8 finish. But they share the same pic on the website.
Download their catalog and print it, or ask them to post you one, or request when you order.
Their printed catalogs are in B+W. Downloading and printing one will be in color.
I am yet to find another supplier that comes even remotely as close to what they have. Heather is just great to deal with too.