Hey Preston,

Sorry I took so long to reply. I blanked out. :P Anyway, I am not 100% sure. I am going to check into this when I purchase my new 580 EX II. This should be some time next week. I don't want to sell all of my flashes (and have to repurchase) if I can avoid it. Going sales prices on ebay are about 300-350 (if you are lucky) for a 580EX....the cost at B&H is 450.

James