I have seen one of these that had a control that was not able to do contouring. (i.e. linear interpolation only will not cut arcs) I'm sure there were different controls with different capabilities available on these units when they were manufactured. Just make sure it will fit your intended purpose. If it is in working condition, you should be able to recoup your investment without much of a problem. A manual bridgeport type mill will run you at least $1K.
Also, don't forget to check the taper of the spindle. R-8 tooling is cheap (realtive term) compared to 30 or 40 taper tooling.