In my case, I tend to look at a number of factors, feedback being one of them. I also look at messages here (the search function can be your friend), but also the way the item was listed on eBay. Is the picture the same one used the last time the chip was offered? Is the information on the chip complete, or does it seem more like hype? Does it seem like a bargain or does it have that 'too good to be true' scent around it?

I can say that I have been very happy with nearly all of my purchases on eBay. I have yet to have a sour experience (there have been a few where chips were delayed, usually due to issues) and most every chip has been almost or exactly as described. Now, being strictly a buyer, I realize that my experiences are different from those who are sellers, but I have worked to maintain good relationships with those who I've purchased chips frequently from.

There are a few sellers on eBay that do ring alarm bells with me, either from the way they advertise their chips or from the fact that the same chips keep coming back up over and over again. Fortunately, those are easy to keep an eye out for... and I wish eBay had a way to block those sellers as easily as sellers can block bidders. *chuckle*