The used market has been quite good to me. My current system contains several pieces that were sourced from Audiogon; and so far almost every transaction has been a success. Only once did I almost get stiffed, and there have been a handful of minor shipping issues. The used market has allowed me to own gear that would normally be out of my reach.
Pieces in current system that came from the used market are:
Jeff Rowland Consummate pre-amp
Jeff Rowland Model 5 amplifier
Mordaunt Short Performance 880 speakers
JVC-XL-Z1050TN CDP
Nikko Gamma I tuner
I have bought and sold a nice stable of used gear over the net too. Includes product from Quicksilver, Well Tempered, Electra-Print, Art Audio, Cabasse, Tara Labs, GR Research, AES, Audio Innovations, Acoustat, Snell, Eminent Technology, Koetsu, Dynavector, VPI...and a few others that escape me.
All in all the used market has been good to me.
Regards
Mister Pig