There is some mention of the MCK-142 in this thread, but it hasn't been mentioned in quite a while.
Welcome to geekhack! We'd love to see some pics of your keyboard collection. 
MCK-142 Pro, Acer accufeel clicky membrane (which maybe i should start another thread about clicky membranes? and a whole bunch of things, like northgate omnikey ultra, omnikey evolution, and recently i'm taking apart a keyboard here are the pics:
http://flickr.com/photos/20106852@N00/sets/72157604773109093/These switches shown in pics above have ALPS logo on them. (look carefully you'd see it) it's made in March, 1992. Switches under the MCK-142 Pros looks just like these but the markings are slightly different. I'm trying to take it apart and make a mod, sort of like steampunk keyboard from the steampunk workshop.
I used to study in Purdue University where all the unwanted equipment is dumped in a warehouse where students can go buy for cheap. I would go through all the keyboards and pick the clicky ones. most of them were omnikeys. Recently a Notre Dam guy told me that they have the same type of facility for old used equipments. I last visited several years ago. they had mountainful of IBM Ms.
Ah. The good old days. I buy them for 2.50 each and sold them on ebay for $32.
I suppose I have one of the very rare split ALPS keyboard from northgate, the revolution. It's still brand new in box. in fact, I am a pack rat and I used to have a ton of keyboards in a storage but eventually couldn't afford to pay for the storage and lost all of them.
By the way, that amazon review of MCK-142 is made by me. the keys are asian layouts and I called the company a few years ago they told me that the demand is so weak that they are not making another batch of these. So I think maybe they used different switches for different batches of keyboard and I ran into one from the batch with software spring switches. I really prefer those lighter ones. they click the same way but they take less energy. Right now I'm typing on a Cherry blue at work (M10) and the resistence is a bit too much for my taste. the click is nice and light, though.
A guy on the 'net takes cherry switches apart and shorten the string and the stem to make the resistence lighter while still having a click.