I was just reviewing this older thread trying to decide what my next keyboard should be. I have been using the Typematrix 2030 since 2013. Before that I used a Kenesis Freestyle. Overall, I've been pretty happy with the Kenisis. However, my Typematrix is no longer consistently responding to keys. I find I have to type my passwords multiple times, because if I don't press down at just the right angle, it won't record the keypress anymore... I had to do a warranty replacement in 2015. But overall, not bad.
But it has been enough years, I figured I better look and see what else is available before just ordering another...
One of the issues I have is my thumbs get sore very easily. Some days I can't use my right thumb, and some days my left. For awhile I used touch pad only for my mouse, but eventually the tapping started bothering my fingertips, so I've switched to a horizontal mouse. It has been decades since I could use a regular mouse for more than an hour or two.
I notice 99% of my typing on the Typematrix is restricted to the letters and number rows. I almost never use the function key row, because that requires taking my hand off the home position. And if I have to use any key other than the space bar below the letters, I have to take my eyes off the screen, as I shift my hands around and determine what will cause me the least amount of discomfort. Likewise I almost never use the far right column, because again it is just too much of a reach and requires moving my eyes off the screen.
An exception to this seems to be the arrow keys. I will take my hand off the keys and use those without even thinking about it, just like using a mouse. As far as my mind is concern, it acts like those keys are completely separate input device.
Of the other keyboards I see people mentioning, I looked at the Dropdox-EZ, and quickly concluded my thumbs would make that keyboard unusable. The plank seems like a logical choice, but the lack of a numbers row seems like it would make software development virtually impossible. I can't really see how I would be any happier with that keyboard than a Typematrix.
Really, my ideal keyboard would probably be a split Typematrix. Give me a little more freedom how I hold my hands relative to eachother, and it would help avoid some of the stresses. Non-staggered definitely works better for me than staggered. But I can't really find that type of product. Are there other keyboards I should be looking at?