I've had nothing but good deals since 2002 here on ASC; heck I even ship items before I receive payment so I can bill for exact postage, assuming a user has good feedback.
I'm seeing a lot of the problems being new players dealing with each other, and issues arise due to poor communications or players selling broken gear. Also way too many new players who get av'd and have a tiny hiccup in a transaction are too quick on the draw when it comes to posting their dirty laundry in the General section ie:
"Ultra Noob screwed me, won't answer emails, tracking number doesn't work"
Only after about ten posts does the author then admit that it's only been two days since they sent the money, and the seller was just at the cottage for the weekend....