In REA's auction last night a '51 Bowman Mays SGC 3 sold for
$24,600, almost $7K higher than a
'51 Bowman Mantle PSA 4.
Strong price for the Mays, which sold for higher than a
'51 Bowman Mays SGC 6 in the same auction, and a relatively weak price for the Mantle. Not sure if this is just an outlier, or if Mays is actually closing the gap with Mantle, but you don't see a Mays Rookie outsell a Mantle of a higher grade often.