I think that the slab plastic, the toning, and the fact that we only have on screen pictures, have all played against us to hide marks that we can't see, and so make grading by us more difficult.
Therefore, don't feel too bad if you disagree with PCGS, who had the advantage of examining raw, under ideal lighting conditions.
Nevertheless, I also think that some CCF'ers are occasionally more accurate than the
TPG's.
With rare coins in high MS grades, fine differences of opinion can have huge implication in price differences. Negotiating a sale for such coins can be a risky business. I am glad that I am not a professional TPGrader.
Safer and cheaper for most of us to stay in the AU and lower MS grades.