I bought one of those Unicomp keyboards and I was very disappointed
with the build quality. It looks like they just made a cheap plastic housing
for the keyboard but there was none of the heft of an original IBM model
M.
I have a Unicomp SpaceSaver 104 and a Customizer 104. I would not buy the Customizer
again; it has all of the bulk of the classic Model M without the same build
quality. On the other hand, I love the SpaceSaver -- while it's likely not as
effective for self-defense as the classic Model M is, I love typing on this
as much as my ~30yr old IBM keyboard (which still works great!), and it uses
less desk space, and is natively USB. It also doesn't feel as flimsy as the
Customizer does, probably simply due to there being less plastic overall.
I also use a Das, which I don't like typing on as much as the SpaceSaver but
it is extremely well built. Maybe I'll replace all the key switches in it
with these green ones if they're more like buckling springs!