Guess I've just had great luck with paypal, never had a problem with getting my money back, nor did I ever have to get 3rd party involved. I've only had to open a case twice, I guess since I didn't receive anything it was easier for paypal to side with me. I'll continue using Paypal until they give me a reason not to.
You were the buyer in any sour situation? If so then yes you are remarkably lucky that paypal hasn't decided to to lend its mighty "fuck your shit" hammer upon your head, most likely just done out of spite and lulz.
They helped me once, likely to lull me into a false sense of security, and then it has gone south ever since then.