It worked well when I got it, so I haven't had occasion yet to open it up to check for repairs/mods. Part of the outer clamshell wiggles a little, but that is only noticeable when I pick up the KB; not when I have it on the desk, typing.
Moistgun, maybe some other folks have had better luck at thrift stores etc, but I've never found a KB worth buying at the stores around here. Maybe if I luck out I'll find one at an estate sale or surplus, but almost 100% of the used keyboards around are cheap rubber domes. I picked up my M for less than $40 on ebay, and I've been very happy with it!