[parkher]

T3 was never rooted, as far as I know, and that is why I never bought it. I wanted it badly, but I had no use for it, not rooted. I have only rooted T1 and T2. Seven of them (I gave some of them to my family).
And I was rooting for Sony. I greatly admire Sony for not betraying the purpose of e-ink, for integrating lights into the cover rather than into the e-ink screen.
But at the same time I cannot understand why they decided to go under with their e-reader business rather than to make android open. They saw that people were buying only their devices that could be rooted, didn't they? They deliberately made a newer T2 firmware modification making it impossible to root T2 - and nobody bought those T2s, only the T2s with correct for rooting firmware. I was quick enough to get two, but I had to buy two more from USA instead of Europe, hunting for the correct firmware version.
As to the devices with lights - so no, a good external clip-on light is so much kinder to the eyes and makes the screen look so much more like a paper page.
I demonstrated this to several of my friends who did not believe it before they saw it in the dark. I got them converted. Of course, I try to avoid the need for a clip-on light, I don't read paper books with a clip-on light either. To me, an e-ink reader with light is an oxymoron - it defeats its purpose - e-ink was invented to make the screen not to emit light. And that is why we are paying big bucks for it.
You can hurt your eyes with a tablet of better specs for a half or a third of the price.
I never work with any documents, for that I have several computers with multiple big screens. Yeah, hurting my eyes with better specs…
So for me e-reader is only for reading fiction.
And I like wide margins, so 7.8" Ares is perfect in portrait orientation.
And even Alita is great with even wider margins. With Alita I read in single column in portrait orientation with very wide margins so that the page in the middle of the screen is of the size of a real printed book page.
But I have also some pdf books (well, many), and they contain scans or pictures of paper book pages (not yet OCR'ed) - so 10.3" allows to read such a pdf with book pages of the original size without any zooming or shrinking. These pdf files are about A5 in page size, exactly the size of 10.3" screen.

And I sometimes use 10.3" for sheet music. I was thinking about getting a 13.3" (or what is its size) e-reader for that, but I am using a 24" AiO computer with touch screen hanging conveniently instead, so it is good not only for sheet music but also for various music software: DAWs, virtual instruments, etc. Such a screen allows to have two pages of A4 sheet music side-by-side in perfectly natural size. Again, not so many hours a day at this, so e-ink is not crucial.