I was convinced by a friend who wanted to buy a TypeMatrix 2030 to buy one too so that we could get a discount. Here is a review of it, after roughly one month and a half of nearly exclusive use. The version I have is the blank one (because looking at the keyboard is a bad idea, and because it's kinda pretty).

To give a bit of background: I've been using the Dvorak US layout (with dead keys to get French accents) for about two years. I touch-type, and can reach around 110 WPM on speed typing games (but am nowhere as fast in real life usage). Before that, I touch-typed on the French Dvorak layout of Josselin Mouette adapted from that of Francis Leboutte (which got removed from Xorg for stupid reasons), and still before, I hunted and pecked on the Azerty layout. I love exclusive keyboard usage whenever I can afford it, and hate having to move my hands to reach things away from the home row like the arrow keys, the numpad, or (gasp) the mouse. Oh, and I love the command line and commandline apps, and use vim.

General comments

The blank version of the keyboard is very stylish (though it's sad that the design is so asymmetrical). It is guaranteed to confuse or impress people, which can be fun, and, if you're using an alternative layout, it is a gentle hint to other people that they'd better not try to use your keyboard.

The keyboard does have some unexpected features, like a hardcoded Dvorak layout that you can toggle and which is managed by the keyboard not the OS. In other words, turning this on will make the keyboard interpret what you're typing as Dvorak and translate to the OS, which will do what you expect if the OS is configured to receive Qwerty. Of course, if it already expects Dvorak, then you get garbage. This is useless to me because I need non-standard dead keys (and seldom have to share my machines with Qwerty users anyway), but can be useful to others. Or you might also be disgusted to see that the keyboard tries to do some fancy logic like this. Or maybe regret that since it does, it would have been cool to also have fancy features like the ability to remap keys and record macros on the fly...

There are a few multimedia shortcuts and all. Some of them are actual multimedia keys which you can map to whatever you want, and some of them (like cut, copy, paste) are hardcoded sequences which are indistinguishable from the separate keys. The precise status of those keys is described in this document.

The dots on the index home row keys are there, and at the center of the key, which can be surprising if you expect them to be at the bottom. There is also a dot on the delete key (which I don't see the use for), a dot on the lower row pinky key (which is '/' on Qwerty but 'z' on Dvorak) which I find useless and slightly confusing, and a dot on the down arrow (which is a nice touch to help you reach those keys without looking whenever you have to use software which requires them).

The TypeMatrix 2030 does not have N-key rollover (NKRO). That's a bit disappointing for a keyboard of this kind...

Adaptation period

Adapting to the TypeMatrix 2030 takes a bit of time. It's nowhere as hard as learning a new layout, but it is definitely not instantaneous, and you might want to count one week before you're up to speed. Here is a list of the things that I had to adapt to:

Touch

The key touch isn't really special (and I'm not really picky about that sort of thing anyway), but it is slightly hard. This, along with the fact that the position of the modifier keys somehow confused me at the beginning, meant that my wrists suffered a bit and that it was literally slightly painful at the beginning. This didn't last, fortunately.

Modifiers

The main modifiers that I use are left shift, left control, super, alt, and altgr. Finding out where there are to be able to press the right ones without even thinking about it takes some time.

Enter and backspace

One of the most original things about this layout is the fact that the enter and backspace keys are in the middle of the keyboard (and pressed with the index) rather than far at the right (and pressed with the pinky). This means that you have to replace the very low level reflex of reaching for enter when done and backspace when wrong by the reflex of going at the center of the keyboard.

Matrix keys

The other important feature of the keyboard is that the keys are in a matrix (duh). This isn't that much of a deal, except for those keys which seem to be off by one relative to their position on usual keyboards. The worst for me was the right half of the lower row, and numbers.

Real touch-typing

Unless you're completely touch-typing (and it's easy to be mistaken), the absence of markings will make you notice those keys where you sometimes peek at the keyboard. In my case, the letter keys were fine, but not the numbers and symbols...

Assessment

Overall, I have to admit that I am not that enthusiastic about the benefits of this keyboard. Though aligning the keys in a matrix seems more logical, I do not feel it makes much of a difference. Maybe it's better somehow--but then, maybe not.

Another slight problem is that damn enter key. Putting it in the middle seems like a good idea; however, this means that pressing it by mistake still happens now and then, whereas I never had this problem with a regular keyboard. Yes, it's easier to reach, but then the usual enter and backspace can also be reached with the pinky almost without moving the hand, so it's not much of a benefit.

My main disappointment, though, is that it is doesn't make you type faster, or give you the impression that you're typing faster, or make you feel better, or whatever. It feels like just another keyboard; a good keyboard, with a cool design, but definitely not worth the effort of carrying it around when you're using a laptop, and probably not worth the money and adaptation time. Granted, if you have RSI, you might want to see if this helps. If you do most of your work on a fixed workstation and you're willing to pay extra, this might still be a reasonable choice. But otherwise, if you're just a normal typist not especially dissatisfied with normal keyboards and just intellectually satisfied by the TypeMatrix design choices, if you're using a laptop or multiple computers, don't buy it and expect it to be enormously better to use. If you're like me, you won't really notice much.