The top sellers are PCGS and NGC and not because they are actually the best. It has to do with money, dealers have picked these two and both companies are always up to something. NGC is the ANA's pick for grading service. PCGS belongs to a conglomerate of hobby selling companies. I think both companies have conflict of interest problems, that may some day get them in hot water. I feel the better graders and the people who have been doing it the longest work for ANACS as well as the newer ICG. Some of the best graders in the U.S. work for both companies that seem to be a lot more on the up and up. Even better learn to grade yourself and go cherry pick a raw one or one that was graded wrong.