The 7-colour version doesn't support partial refresh and has a 15s refresh time (~0.067Hz refresh rate), so you'd want to be a really confident touch typist.

The Freescale i.MX508 controller can do 8fps. It seems completely capable of displaying vim, but is monochrome. Here’s a video:

https://m.youtube.com/watch?v=0DVlGZ3_d3Q

I’d love one of these with a full keyboard, wifi and enough of a terminal emulator to ssh somewhere.

I was chasing down this route a while ago with a Waveshare touch screen and a RPI3. I was wiring stuff up on a breadboard and was so stoked when things worked. The next level is that you send a schematic into a custom circuit board company and they send you back a PCB. The future is that we custom print open source PCB designs, solder our RPIs and Touch Screens on and bam we have custom brewed machines.

As an alternative approach, I mounted my 2012 Kindle PW, a raspberry pi, and my split keyboard (diverge 2) on a folding guitar stand.

And I mean, it works: https://i.imgur.com/FNbKA0b.jpg

Vim certainly makes the latency tolerable.

Not e-ink, but you can get a RasperryPi case with a built-in display along with battery pack. Pairing with a 40% keyboard gives a nice, portable environment.

Great video on these sorts of displays, what they're capable of, and perhaps some inspiration for any hobby projects: https://www.youtube.com/watch?v=MsbiO8EAsGw&t=617s