Ahh, the wonders of MAS...mandos come, and mandos go, but the syndrome lasts forever. The F-4 was traded for the OM; the OM was part of a three way deal that landed me the F-5.
All the trading, selling, and buying were done through the Cafe Classifieds. All were hassle free with everyone happy at the end of the deal. I can't imagine ever using another method for internet based sales!