I don't understand what the advantages are over Servo's inbuilt web browser¹. So far they look the same when opening but the inbuilt web browser is more stable (I see rendering bugs with Verso and it panics when entering a domain without the http(s):// prefix).
The latest keyboard version 3.0 is more standard. The swapped control vs caps lock position is something one can probably remap in software. The apparent lack of page-up/down and home/end keys would be more of a problem for me, though.
The default firmware uses Hyper (the arrow pointing up and to the right) plus left/right for home/end and Hyper plus up/down for page up and page down. I'm not sure it's good enough either.
Main benefits are a fully mainline Linux kernel plus UEFI: You can throw a standard arm64 image at it and it will directly boot and get updates forever - no custom images with special bootloader setup and downstream kernel needed.
¹ https://servo.org/download/