Note that in terms of performance they would be ranked
3100
4000/200 slowest
4000/300
4000/90
So if you can find a 4000/90 that would be the way to go. Also the 200 and
300 are Qbus based and thus not easy to attach SCSI disks to. All in all
you want a 4000/90. (or 4000/105, or 4000/95).
--Chuck