M700 is their least expensive mono blocks and they do sound good, but their bigger brothers like M1200 and BHK 300 are in a different league. People likes PS Audio products often do upgrades and they have generous upgrade program. Therefore many trade-in such as M700 ended up in the used market.
If the PS Audio Stellar 700M is as great as all the reviewers say....
...why are there so many used ones for sale?