Ebay is a big nono for me, I got scammed when I was buying a motherboard for my PSP there...
I wonder if all OEM Q6600s ship from NJ, because if they do then I have a pretty good chance of stumbling on a good one...

I might also go to Fry's and ask if they have some of the lighter blue boxes left, which indicate a lower/better batch. This seems unlikely because last time the guy was like "I'll see if we have any in stock... we might have gotten a new shipment" -.-'