I've been buying/selling on eBay for about eight years (sold seven items in
the last three weeks, bought about the same).  I have never been 'stiffed'
on anything in either direction.  To me the rule has been common sense.  If
it looks to good to be true it probably is.  When buying and the is ANY
question in you mind about the seller, DONT BUY!!  If questions about the
tiem itself ask questions BEFORE bidding or buying.  Many years ago I had
one item I bought that didn't show up.  I'd given up on it when it showed up
in the mail better than three months later with a note enclosed explaining
that the sellers house had burned down, computer and all.  My item was saved
because it was already packaged and in his vehicle to take to the Post
Office at the time of the fire but he had forgotten all about it until he
found it in the trunk, added the note and mailed it.  And a recent purchase
turned out to be more faulty than the 'as is' sale had claimed.  The seller
and I agreed on a solution that we both felt was fair, didn't need to
involve eBay at all.

I've completed around 100 eBay transactions over the years (feedback at 76
right now) and I don't discourage anyone from using eBay.  As additional
protection you can use PayPal and pay with a credit card, giving you two
places to 'back out' a transaction if there is a serious problem.