If you're familiar with Cherry's MX brown switches, you'll understand how the MX clears work. They have a similar response curve, with a tactile "bump" that marks the actuation point and a small dead zone before the return point. Also, like the browns, they don't produce an audible click upon actuation. That means you get plenty of tactile feedback but quite a bit less noise than with certain other mechanical switches, like the Cherry MX blues and IBM's old-school buckling springs.
The difference between the Cherry MX browns and clears is simply this: the clears have a more rigid spring driving the mechanism. Where the browns require 45 g of force to actuate, the clears need 65 g. That makes the clears the springiest Cherry MX switches after the Cherry MX greens, which need 80 g to actuate (and which click audibly when actuated).
The extra springiness means the clears require more effort to bottom out (that is, to push down as far as they'll go) than the browns, which is a good thing in theory. You see, one of the advantages of mechanical keyboards is that keys don't need to be bottomed out in order for key strokes to register. Because the actuation point is somewhere above the bottom-out point, users can calibrate their typing style to apply only as much pressure as is needed. A touch typist equipped with a good mechanical keyboard may simply skip from key to key without ever pushing down all that hard, thus warding off fatigue.
The other extreme is to bottom out with each key stroke, which is problematic because there's no limit to the amount of pressure one can apply to reach the bottom-out point. One can therefore type much too hard and get tired very quickly.
The tougher springs in the Cherry MX clears make the aforementioned calibration process easier for the user, since they put up more resistance and make the actuation point more easily discernible. It's sort of like how flying a plane with a joystick is easier than with a gamepad's analog stick. The analog stick takes less effort to manipulate, but there's a big precision tradeoff.
The downside of the tougher springs is that, if you've already calibrated your typing style to something with a lighter touch, Cherry's MX clears can feel a little too tough. Even after several days of using the clears, my fingers were just not happy about the extra workload. Going back to a Cherry MX brown keyboard (or something based on Topre switches) felt like blessed relief. While I did bottom out a little more, I could type faster and with less effort.
Now, I have small, dainty hands, and I've been using those other, lighter switches for much longer than the clears. I can totally see how someone else—maybe a larger dude with more muscular mitts—might prefer the clears. Their response is undeniably more distinct, and they can feel more satisfying to type on, almost like old-school buckling springs. Also, they seem to be a little quieter, perhaps because they minimize bottoming out.
The proverbial white whale has surfaced, and it's not quite the be-all, end-all of mechanical key switches that I expected. For my own use, I'm probably going to go back to something with either Cherry MX brown switches or Topre's capacitive electrostatic doohickeys. And for a first-time mechanical keyboard buyer, I'd also recommend something less daunting.
That said, the Code keyboard's appeal is undeniable. If you don't mind being a little heavy-handed, this is a terrific purchase even at the steep $150 asking price. The build quality is awesome, the Fn key shortcuts are delightfully convenient, and the added flexibility offered by the DIP switches and the cable-routing channels are lovely touches. Even the backlight controls are well thought-out, and the backlighting itself looks surprisingly classy.
My only wish is that WASD Keyboards made one of these things with Cherry MX browns. Then again, the company's WASD V2 keyboard, which is available with the browns, is almost identical to the Code except for its lack of LED backlighting—and as a touch typist, backlighting is something I can easily live without. Come to think of it, the WASD V2 is probably what I would buy if I had $150 to spend on a keyboard today.