Learning about this for the first time, do you use the TapXR or the Tap Strap? Are there any tasks you do/not use it for, or environments where it functions better or worse? Can it work single hand or with both hands (and a second device)?

Those require a surface to type, right?

Watched the video and super excited to see where tech like this ends up in a few years. Was on the quest to find a split keyboard last week and ran across this. Ended up with a UHK, but man I thought hard about buying one (pair) of these. I was just worried about dust, dirt and overall longevity. Seems like something that would need to be worked on every month or two. The kit is reasonable and might be a fun (next) project.

https://svalboard.com/

Would be interested to hear about anyone's experience that owns one of these. How do they hold up? How long did it take to get used to using? Would you recommend to a friend?

I'm not aware of any production version of Chordite (that this design is based on) as of now; but in the wider family of chorded keyboards, the one with a production version that I'm aware of is the Twiddler.

No more physical support for the hand than what's seen in the vid. You can check more info in the github repo (https://github.com/akavel/clawtype) and on printables (https://www.printables.com/model/1231156-clawtype). The strap and the plate under the wrist seem enough that I'm not looking to improve on that at the moment; but I still need to test this version on some longer usage sessions. Interestingly, the original inventor and patent owner (https://web.archive.org/web/20220201061603/http://chordite.c...) has a design that doesn't even use a strap, but I didn't explore this direction yet (and honestly not yet even sure how to crack it). I know of another designer who's trying to iterate in that space: http://blog.russnelson.com/chordite

As to resistance, there's a balance to be adjusted between having the buttons too easy or to hard. This seems in main part to need to be adjusted by their positioning though. If too easy, you'll press combinations/chords accidentally too often. If too hard, it gets tiresome and annoying. Maybe there's some better placement possible, haven't found it yet. The switches currently used are Alps; they have dimensions which make them a good fit for this particular design; Cherry MX are a tiny bit too big and would require some rethinking.

As to 2 hands, the whole point for me is to have my main (right) hand available for other use, like drinking water, or otherwise supporting myself in the physical environment around. So I'm not currently interested in two-handed.

As to the number of keys - the four fingers seem busy enough; on the other hand, if you could fit smaller switches around (as in the DataHand design https://en.wikipedia.org/wiki/DataHand - see also 3d-printed clones on the internet - _edit:_ e.g. the https://svalboard.com, as mentioned by someone else, and lalboard https://hackaday.io/project/178232-lalboard-ergonomic-keyboa... as respectfully linked from therein), maybe you could try working with that. The obvious extra possibility is the thumb as you mention - it does feel like something could be added there, though it also sometimes helps a bit in holding the device. The original Chordite designer managed to somehow do it without a strap, but his reasons to not use the thumb are somewhat confusing to me.