They all generally offer opinions of coins but not as part of the submission process, though I always thought they should. There are sometimes designated times when folks like David Hall, Dave Lange, and the ANACS graders will examine and tentatively grade a limited number of coins. They could be submitted subsequent to that but their opinion has no binding nor should it, but it is definitely a good discriminant. The folks administering the submissions are largely not numismatists or at least are not in positions to render any opinions on the submitted coins and their likely certifiability. At the shows, however, you have a high concentration of profressional and semi-professional numismatists, many of which will look at a coin or two to find gotchyas when they aren't too busy. Find a specialist, particularly a guy/gal whose table suggests he/she regularly submits to the TPG of your choice for the series of interest.
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