While doing all my research and making inquiries, I ordered an off-the-shelf Unicomp SpaceSaver from them and it arrived today.
I've only been banging away at it for half an hour so it's obviously way too early for me to judge how much I do or don't like the feel (though so far there's a bit more resistance to the keys than I would have thought would be optimal). The noise is certainly substantial.
What jumped out at me the moment I put it on my desk, however, is how really shoddy the workmanship is from a cosmetics and mechanical point of view with respect to the keys and case based on what I can see (and hear I might add). The photos on their website show deviations such as pits on the top surface of the case (especially in the areas above and between the Function keys), which are of course the result of a lousy mold. I figured it may look worse in the photo on the web than in real life. Well, it turns out it's just as bad in real life. Moreover, the keys themselves are really poorly made -- the tooling of the mold and attention to quality control is pure crap, there's just no other way to say it. Many of the keys have little plastic nipples hanging off of them from the production process (injection molded plastic). The Space key even has plastic hanging off the bottom edge on the left side like a wing -- again, left over from a very lousy injection-molded-plastic manufacturing process. And these are not like the little nipples of rubber that you get on, say, brand new tires on your car, which will quickly wear off from normal use. My choices are to live with them for perhaps years, or get out my X-Acto knife and clean up -- or finish -- their remarkably lousy manufacturing process.
Here are a few photos of my new Unicomp SpaceSaver that arrived today:



Almost everything you see in those photos that so much as looks like it
might be a piece of plastic hanging off the side of the keys is in fact a piece of plastic hanging off the side of the keys.
Based on the cosmetics alone, I'm thoroughly unimpressed. They should be ashamed using the IBM Model M namesake in their marketing and then ship out a product that looks like this.
Need I mention the poor alignment of the keys, too -- the fact that they move out of position substantially? Check out the right-hand Windows key in the second image. I did not deliberately twist the key for the benefit of that photo -- I just happened to notice it after I took the picture. Look at the position of the Space key in the third photo. Again, I didn't do that either. (Hey, maybe this really is part of the original design. Maybe the pits in the top of the care are, too -- but why do I seriously doubt it?) But plastic nipples hanging off a dozen or more of the keys and a wing of plastic hanging off the Space key? Give me a break. $7 keyboards at the local office supply store would never ask you to put up with this kind if insulting workmanship.
And I'm pretty certain, without needing a Model M here to compare, that the Model M never had this kind of "cheap plastic" sound to it. I'll bet anything on that. But that’s another matter. And maybe I'm wrong on that.
Thoroughly unimpressed overall.
I'm now going to ask CVT to customize an Avant Stellar for me to move the backslash-pipe key to where the "local menu" key is, and to change the existing backslash-pipe key to an extra Shift key (so I can do my thumb-across Ctrl-Shift trick). Or, maybe I'll do that with an Avant Prime and see if I can either live with the beige color, assuming I like the keyboard.
And perhaps look into the Cherry.
I'm just not impressed here. Typing away, this is not the best keyboard on the market. I can say that even in the absence of having tried the others hey. Heck, the keys move around too much for it to be up there with the best. And this noise and feel are "cheap" to me. Maybe, for all I know, they went down in quality when coming out with the SpaceSaver -- maybe the Customizer is better manufacturing quality.
I'm just not impressed with what I have here. It’s a shame, too. I really wanted to like this keyboard, have one sent with grease, and call it a day. I actually do have a business to build here. I’m just looking for a really good keyboard and then I can go back to work and forget about this issue altogether… and work!
Maybe in time the "feel" will overwhelm me, and I will in fact get out my X-Acto and clean it up (and what... work on it with it upside down so all those plastic pieces don't fall right into the keyboard when I slice them off? ). And have them send me one with grease in the keys (at which point maybe I can also place a "special order" for one without plastic hanging off the keys, too).