In your experience, is there a preferred Third Party Grader, such as PCGS or NGC, for $50 American Gold Eagles (or American Gold Buffalo)? Is there a appreciable difference (cost-wise) between the two for this series? If so, is it worth it? I have had both over the years for silver dollars, would like to get some input.
In that case, you have to ask yourself: why are you buying? By that I mean, are you buying for investment? Are you buying for a registry set? Are you buying to buy gold? In each of these cases, you might get a different answer - and sometimes the right answer is to just buy it raw.
If for gold investment, all you want is certainty it is real. As long as it's a recognized name, TPG will not matter. The differences come in the grades and the hobby's opinion of grades. If I wanted slabbed gold to prove it's real, any big 4 would be fine to me.