I don't think this is any kind of shocking revelation that PSA sells for more than SGC in any set where there is a decent number of registry collectors. I am kicking myself for not at least putting in a snipe on the SGC 50 1915 Matty Cracker Jack card that closed at $1,213 on eBay a couple days ago. The 1915 Matty CJ is one of my white whales, but I didn't bid or put in a snipe because it was already at $900 with several days remaining and I figured it would close far out of my budget.
http://www.ebay.com/itm/1915-Cracker...vip=true&rt=nc