I’m not the dude above but I did buy one and I’ve been having too many hardware issues to keep it. Bluetooth is really flaky, fingerprint reader works very infrequently, panel uniformity is worse than the pixel 2XL. Basically the only thing it has going for it is the software and form factor

In comment options there’s both the nav bar and the option to use the volume rocker to scroll

Quentin sells prebuilts here: https://bastardkb.com/prebuilts/

I use a prusa mini. It’s really reliable and the build volume is enough for split keyboards

I’d strongly recommend against different layouts for different keyboards. I tried to do this with QWERTY on my work laptop and Colemak-dh for my ergo and it just makes you worse at typing on both. I guess if you’re around 40 wpm it wouldn’t matter but there’s no way you can retain 100 wpm muscle memory on two layouts