I feel compelled to state "Buy the coin, not the plastic".
Even the best
TPG's make mistakes (a recent dateless 1917
Standing Liberty quarter mistakenly attributed at 1916 comes to mind) so absolute trust in a third party grader should be avoided. Granted most of the attributions are correct, there are still issues with what the grade should be. As long as you are educated about what you are purchasing, especially if it is a coin that is stretching your budget, you can make purchases that will satisfy you.
I personally buy slabbed for authentication purposes rather than grade and even then I study the coin before any purchase is made.
My favorite graders, hands down, are on CCF. You get a range and reason for the grade - as well as education along the way.
