I am also not sure if the SoCal (small) stamped discs are Pre-Release. I was under the impression that ALL 160 pre-release Destroyers were stamped with the large and ugly US MASTERS rainbow stamp. All the other champ destroyers are CFR - NOT pre-release. Ebay at your own risk!
the ones i got all have the so cal mini stamp and came with the certificate thingy saying that they're 1 of 162. i guess that could have been a crock of poopy, but i'm gonna go with.... you're wrong.