I bought a Pomera DM30 instead, and I love it. I haven't seen it mentioned in this article or thread, so I thought I should call it out. There is no US keyboard version, but the learning curve for the Japanese layout wasn't too bad, and otherwise it's perfect: small size, e-ink screen, plaintext editor saving files to onboard flash (easily accessible with USB) or SD card. There is no pointing device, but (and I'm saying this as someone who wrote a novel in Vim) the editor provides enough commands to get around a document without too much trouble. More than anything else I think it's the screen size that discourages pathological editing-as-you-write, especially if you pick a comfortable font size.
The DM30 is a serious tool for people who want to get work done. If the idea of the Freewrite appeals to you but you feel like the Freewrite itself is bullshit, check out the DM30. It's also significantly cheaper.
edit: looks like it's discontinued, RIP: https://www.reddit.com/r/eink/comments/p5zg6s/fyi_the_kingji...
Get one while you still can...