The Mk lll is a 2 track only model. It doesn't have the 4 head configuration of the previous models which can playback 1/4 track tapes also. On the other hand, if 2 track is all you want, they are more recent and could be in better shape. When I was considering buying an Otari, there were enough of them out there for me to wait till there were ones in my general area so I could actually look at them. I went out and looked at 3 of them and they were all in pretty bad condition (at least in bad enough shape that I didn't feel like they were worth biding enough to assure I would get it).