Well, I have over 600 feedback on ebay... from buying and selling. Mostly Buying though...
I would NOT buy a car on ebay... I have enough problems trusting a dealer when I'm looking them eye to eye during a sales pitch... call me paranoid.. I just wouldn't risk buying a car on ebay.
I did buy a digital camera on ebay several years ago-- however I would NOT buy most electronic items on ebay... (if it wasn't nonworking when I bought it, it would be by the time my mail carrier got finished with it)
I have bought DVDs, Homeschool curriculum, clothing, books, toys, household items, gift certificates, etc...
I am an ebay addict. My dad has me sniping auctions for him. I beat one person by a three cent bid a couple of nights ago... got a nasty email from the bidder who lost the auction by three cents.

I was tempted to write them back and tell them they can't blame ME because they weren't willing to bid as high as I was.... but I didn't. Just forwarded the nasty email they sent me to Safeharbor @ ebay.