There is a special level of Hell where every computer work-station is populated by nothing but Apple Design Keyboards.
If it's possible for a keyboard to have anti-feedback, that would be the one. There were times when I would swear I had gotten feedback from a key that it had bottomed out and should register, but nothing on the screen - and this was normal for these things over the several I had the misfortune to use, even brand new (other people's boards, I might add - no, I was never dumb enough to buy one). Then there was the occasional bounce.
Keys were mushy AND stiff, with inconsistent switching points as well. It was the typing equivalent of Russian Roulette. To come down from the marvelous AEK and AEK II boards that they eventually superseded made them seem even worse.
Honorable mention has to be given to the original G3 iMac keyboard that Apple also shipped with the Pro Models for way too many years. Not as truly, brain and finger hurting awful as the Design, but still not a great experience to type on for any length of time. I agree that the only reason people didn't complain more about them is we were preoccupied with dealing with the Hocky Puck of Doom - a mouse only Wrongway Goldfarb could have loved.
Oddly enough, the newest Apple Aluminum Keyboards, both stand-alone and those on the new MacBooks and MacBook Pros, are a whole different story IMO.
Upon seeing them I just knew I would absolutely hate them to actually use - flat little chicklet-like keys with almost no travel - pure form over function. I forced myself to try them out, however, and couldn't quite believe the experience, so I had to go back and try them again. It came as an unexpected and rather pleasant surprise - I liked them.
Mind you, if you try to just plain type on them, forget it, but I found in very short order that I was adapting my typing style to sort of glide over the keys, almost caressing them instead of pounding away on them like a normal clicky keyboard. The end result was quite fast and accurate typing with much less fatigue than a normal keyboard. Crisp and precise, yet still soft was the impression I got. I do wish there was a bit of curvature to the keys, but despite this I didn't find my fingers wandering any more than usual - it just required a bit more control and finesse, which came fairly naturally with the soft gliding typing style they seemed to encourage.
I think it's a matter of you either love 'em or hate 'em, with very little in between. I'd have to live with one for a few weeks to know on which side of the fence I'd finally settle, but I'm pretty sure where I'd end up.