Here's a common scenario buyers encounter (I am both a buyer and seller so I know both sides).
The buyers feedback rating is at 98% or 99%, one more negative drops it below the 98% required in order to offer PayPal protection to future buyers.
The buyer pays through Paypal the moment the auction ended but the item arrived in horrible condition, significantly not as described or the item never even arrived. Buyer immediately contacts the seller, he/she is completely unwilling to exchange the item or claims they did nothing wrong.
Buyer wishes to leave a deserved negative feedback at this point, but they are aware that the seller will retaliate with a negative the moment they do.
So what does buyer do?, leave a negative comment knowing full well that they will receive one in return (even though they did nothing wrong but buy from this jerk). No, the buyer will probably leave no feedback comment or a very short positive feedback comment to be safe.
Technically, the buyer should leave a negative to inform other ebay users of the sellers bad business practices, but most people only look out for themselves. Other ebay users may never learn what a jerk the seller is because this happens all too often. Only the bravest of buyers will leave a negative knowing that the seller is most certainly going to retaliate.
This is what's wrong with the ebay community, people live in fear of getting a negative through retaliation.
Anyway, this thread was not supposed to be a comment on ebay or the ethics of buying on ebay. I just wanted some recommendations of reputable ebay sellers, that's all.