I ordered the TypeMatrix 2030 at the end of 2012 and have been using it exclusively and intensively for about 6 weeks now, with the colemak layout (which I was already using before). Thought I'd add my experience here for any future readers:
Ordering and receiving went smooth - it took a bit more than a week I think, since I'm in Europe and it was sent from the US. That cost $30, but that's pretty much what it actually costs (they first sent it to a representative in France, who sent it to my country with the French mail service).
After initial inspection it turned out 1 of the keys wouldn't press down smoothly. This was easily fixed. I removed the keycap according to the instructions on the typematrix site. The rubber dome was placed slightly off-center, so the pin of the keycap wasn't aligned with the "shaft" in th rubber dome. I replaced the keycap while nudging the rubber dome to align with the keycap pin, basically fixing the problem. I really should have removed the rubber dome and re-glued it to the center or so, but this was good enough.
I got a free skin using a promotion code from their mailing list. However, when using it, pressing keys took too much force for my taste (and health).
So I quickly switched to using the keyboard "naked".
I pretty much immediately remapped a lot of the non-letter keys, and after that key placement was very good. Your (well, mine anyway) thumbs can comfortably reach a few keys, allowing you to map some oft-used keys there. For example, I mapped left alt to enter, right alt to backspace, the "desktop" key (right thumb) to control and "shuffle" (left thumb) to alt. This is good stuff. I do feel there would have been room for one more key near each thumb, taking a piece off the space bar, and it would have been nice to split all double-sized keys for more remapping options, but I guess they wanted to keep the layout somewhat conventional. A further minor note: If you want to remap a lot of keys, you'll probably have to use the keyboard in "106" mode -- but you have to put it in this mode every time your computer starts up, but yeah, just a minor thing.
A minor downside of the layout is that some key combos require a twisting hand movement, f.e. pressing shift + tab or ctrl + tab with just the left hand, but I suppose you could fix this by just using the right shift/ctrl in such cases or remapping.
Another minor downside, ergonomically speaking (although I am no expert), is that the placement of the cursor keys requires you to move your right hand/forearm back quite a bit -- they're placed "lower" on the keyboard than normally. This placement *does* reduce your right arm moving to the right like on a regular layout, obviously, but this is the cost you pay for that.
Now I'm arriving at some big problems I have with this keyboard. I want to stress that this is just my experience, and I have suffered / am suffering from mild RSI, so your mileage may vary.
For me, after extensive use, I eventually get pain in the hands - a type of pain I hadn't experienced before with my mild RSI -- The keys require too much force to actuate (specs are 55g +/- 10), and/or the mechanism (rubber dome with scissor switch) is bad for my hands. Perhaps it's bottoming out too abruptly, I don't know. I can say that - like any rubber dome, I guess - the actuation force is mostly up front. The pain feels like it's caused by hard impacts, so that would make sense, but this is all just my personal interpretation.
On the plus side, I do believe the matrix layout is beneficial to reduce weird finger reaches/stretching/angles: The other type of RSI problems have not returned, which were mostly due to stretching my pinky fingers too far away.
All that said, there are plenty of people who have a great experience with this keyboard. Unfortunately it's not good for me.
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Now I'm doubting whether or not I should keep the board. I can return it, but that would cost me about 20 euros and the refund covers only standard shipping (reasonable ofcourse, I'm not complaining), so after all is said and done I'll have paid about 40 euros to try it out.