What's the difference between a PSA 8/9 & 10?

@xgav1337x has a pretty good article about it: www.elitefourum.com/t/psa-grading-standards/15683/1 Unfortunately he (still) has to add the PSA-7 to 10 scans to the article. His video does cover all of them though:

Greetz,
Quuador