Looking for a used AUDIOPHILE AV Receiver

I am in the market to purchase a used audiophile AV Receiver. Price range maximum $800 for a used unit, the less the better.

The most important factor is the audiophile sound quality, sheer musicality that the unit provides, not the features. It should also have HDMI 1.4 at least and also Speaker A/B switch would be a good option as I have 2 different pair of speakers in the front, one for HT (Definitive Technologie BP 7006) and the other for music Magnepan MMG.    

I know some brands like: NAD, ARCAM, ANTHEM, MARANTZ making good audiophile AV Receivers.

What would be the best option for a used unit?

Thanks for any advice.