i have only been burned once in the close to 9 years i have been ebaying.
but in all the transactions i have had, i have had some really good times too.
i bought a monocular-viewer for a toyo camera - one that i know new would have cost over a hunderd dollars new, and on ebay they weren't going for much less than that ... a guy was selling it on ebay - cheep! i bought it - then he realized it was a different item than he had advertised - and rather than call off the whole thing, and risk negative feedback, he sold it to me for the price the auction ended on ... he knew he had sold it for about 60$ less than he could have gotten it for, but he realized an honest deal is an honest deal.
needlesstosay, i don't ebay as much as i would like. kids can't eat a lens