6YE Premium vs not?

[kivie]

I see questions asking if a particular model is of premium version? Is this a thing or a misconception?
If it is what makes one version premium vs non?

[Booty Call Dolls]

Hi,
Per a source of mine that sells dolls in China, the premium line has more detail.
Could be made better too, right?
Have you ever wondered why some TDF vendors are NOT on the 6ye Premium Global list
https://www.6yedollglobal.com/buy.html
but still sell 6ye dolls and can not sell AMOR ?
V/r
Jeff