Experiences Selling Stuff On Audiogon?

all these sales platforms have user data and feedback, so it behooves one to look at that, see the track record of whom they are dealing with 

you can't fake a long positive track record and excellent feedback

I stopped using Useless Audio Mart since I kept getting rogue buyers who never responded to my acceptance of their offers or they never paid after they told me the payment was upcoming.  Yes, AG charges a lot but you get what you pay for.  At AG and Ebay if you make a formal offer it is considered a contract, rightly so.

I've never had a problem with a transaction on USAM and I've bought and sold quite a few times. There are plenty of tire kickers of course, but that's the case everywhere.

Here or USAM are both just fine.  Treat people the way you would want to be treated and you should do well.  However, there are always potential risks that have been well-covered in these threads, like shipping big speakers.  There is a lot you can read and learn here.