Comments mention Pocketbook. How good is it? I’m tempted by 10.3” screen since I read technical pdf’s (think O’Reilly or Packt) a lot and no Kindle is good for that.
I read all my Kindle books on it, it's entirely replaced my paper notebooks for note taking, and all my technical books, manuals and so on have been excellent on it.
Your intuition that this form factor is better for technical PDFs is correct, I think.