I have three mini Samantha's to compare. The differences are CRAZY!
Mattel dolls are more "pink" in skin tone and a plain face mold with very simple details. The PC dolls have a VERY detailed facemold, glass eyes and beige skin tone.
AG dolls are somewhere in between.
Mattel - Pleasant Company - AG
The details are missing in the cheeks and nose in the Mattel Samantha. These are the dolls that were mass produced for bookstores, Target and other sources besides AG.
The Mattel hair is fuller, more coarse and wild! AG has smoother, softer and finer hair.
You can see as your eyes moves from left to right, the details reduce. The face widens and the hair is lesser quality.
There are more ridges and separation details in the PC hands.
AG hands have slight knuckle ridges, the Mattel hands look more like webbed fingers.
PC Sam has no body tag and the AG doll has one tag.
PC Sam is smaller in size compared to AG Sam.
You can see PC Sam's bangs are smooth not puffy like the AG doll.
Mattel dolls have two body tags.