Ahh I’ve done so much research here and tried so many different devices.
* the Kindle Scribe has a great feeling, but the software is lacking, particularly around the writing experience. They’ve released two substantial updates to add missing features, but they’re still far from parity with the writing-first offerings from other companies. Also, critically, only some books - crossword puzzles are their example - support writing directly on the page. It’s backlit and feels great to write on though.
* I used an iPad for awhile and it’s a solid solution. Obviously if you install Instagram or whatever you’re seriously degrading its value as a tool for focus, so don’t do that. I switched away because the epaper tablets look better in sunlight, have superior battery life, and feel much much better to write on.
* remarkable feels wonderful to write on. I returned it primarily because I find the company is not super responsive or forthcoming with their plans for improvements. Also, it can’t read Kindle books unless you first convert them to epub, but if you want to write directly on a book on any tablet, you’re gonna have to convert away from Kindle. If you’re really doing nothing but writing — no reading, no annotation — this is probably the right pick. The writing feel is like a scratchy pencil on paper.
* I would not recommend the boox note line. These are fully featured android tablets, though it’s a mystery to me why you would ever want to watch a YouTube video on an eink display. Anyway, I’d avoid these tablets because their response latency/ghosting is quite poor, which will annoy the hell out of you.
* Supernote is what I currently use and would recommend. Their A6X the only one of these devices that comes in a smaller paperwhite-ish size (though they also sell a larger A6X). You can read Kindle books directly via the Kindle app, though what I wrote previously about having to jailbreak to write directly on pages remains true. Supernote has the most robust software for organizing notes, linking between notes, creating digests of epubs, etc, and I find their file management and sync software to be the easiest to use. Also their nibs don’t need to be replaced, ever. And they’re very directly engaged with the community —- you can find a link to their development Trello on r/supernote, as well as regular interactions between the dev team and the community. Their tablet is not backlit, and it’s not as snappy as the Kindle. Their cloud syncing is not automatic, which can be annoying. Also features an email client and a calendar, but I don’t use those so I can’t speak to them. The writing feel is like a gel pen on paper.
* The kobo elipsa 2e is likely the most direct competitor to the Kindle Scribe. It’s backlit and waterproof, and it’s suite of writing tools, templates, etc is frankly what the scribe’s should have been. Unless you’re really wedded to the (again, read-only) Kindle store, I struggle to imagine why you wouldn’t but this kobo device over the Scribe.
* finally, look forward to the lenovo smartpaper is supposedly the one to watch for later this year. It’s a bit more expensive, but is snappier and received good reviews at CES.
Overall I’d recommend the Supernote. My only complaints are that it’s not backlit and can feel sluggish, but in terms of functionality and support, it’s the best. And if you want a more pocketable device it’s the only option.
One last recommendation — if you can swing it, definitely narrow down to your two or three top choices, then order them all and return the losers. The writing feel is quite different across these tablets and comes down to taste.
Some features I don’t care about, but you might, and should research if so: audio book compatibility, word doc compatibility, audio recording