Well I have, and I can say that I will never get anything from him again.
I won an auction for a derailleur, and after receiving no confirmation or communication of winning the auction I decided to try and contact him. Four messages/emails and almost a month later he writes back saying that he posted the item out almost two weeks prior. Okay, fine I can live with that. Another two weeks passes before the item turns up, and upon inspection of the postmark on the envelope, it showed that he didn't post when he said, but rather almost two weeks later. When I actually pull the derailleur out of the envelope, I don't like what I see. The derailleur has evident signs of wear on the inner of the cage and isn't close to being "near mint" and "showing signs of hardly any use". His photos (which everyone says are so great). This p*sses me off, so I contact him about it. Over a week later he gets back to me asking how he can make things right. I tell him to leave me good feedback, seeing as I paid and contacted him immediately upon the closing of the auction. Well, almost three months later and no feedback left.
Take that (and the other negative feedback he's received lately) as a warning...