Ah this is really cool, quite similar to a keyboard I’m designing - https://imgur.com/a/z31Zfoa - haven’t designed a case yet.

They have taken an interesting approach with thumb cluster, single key on farend and 3 on near end of thumb. I did the opposite of that, on account of thumb being not that flexible in bent position.

Over the years my daily driver has been kinesis advantage2. I tried ergodox but really disliked thumbcluster placement and additional middle keys. I made a keeb.io Nyqist recently and got a few pcbs printed for Redox, need to build that out.

It is really hard to go back to non-split keyboards after using split for a while, and kinesis advantage is still the gold standard imo, concave keywell alone is the reason to spend north of $350 on it.