I had a 3100 on my desk for several years, with an LK201 keyboard and a 19" color monitor, running Ultrix 4.2/3/4 iirc.
It was snappy enough running plain X11 or Athena (Xaw) applications, but Motif stuff slowed it down a bit. I had a tvtwm running a big virtual desktop, an Emacs with a bunch of frames, and a stack of Xterms.
We had a couple of 5000/25's with the multimedia peripherals, but they weren't really worth it. IIRC, our group's server was a 5000/240 (?)
Then we moved to Alphas (3000 AXP, then 4/255), then a Sun Ultra 10, and finally Linux PCs.
