While I have bought Creeds on Ebay in the past, I no longer do, especially for 4 oz. GIT, which has got to be one of the most counterfeited colognes on the market right now.
It's not that I think Ebay is that bad, but the prices never seem to be much less than at legitimate discounters. I know I'm getting an authentic product from places like fragrancex, scentiments, or fragrancenet.
True, buyer protection through paypal is a savior, but it remains a hassle I'd rather not deal with. Although I can honestly say I do not remember ever receiving a fake scent on Ebay, even once.