Well, Bailywolf, here you have upwards of 150 users
of the Sony who don't seem to have much trouble getting Gutenberg files (or any RTF files), on their Readers (there have been a few issues here and there, but not general ones). Compare that to the remarks of a few Reviewers
who likely spent a few hours with the Reader .... Well, you can make that evaluation for yourself.
As for A4 (letter sized) PDFs, no they don't work on a 6" screen, unless you're gifted with micro-vision.
However, that's more an issue with the PDF format not being reflowable, if it were, then the problem wouldn't exist. For things like Manuals and text books, of course, there are a lot of things that are layout dependant, and need to be displayed as they are, and just flat need
to be displayed in the A4 size. I think there's a (huge) market for an A4 sized e-ink device, but that's not what the Reader is aimed at.
It's aimed at reading text, and it does that quite well. If that's not what you need, then that's not what you need, and the Reader won't work for you.
thing can be every
thing. Just the way it is.
Like I say, it won't do everything, but it does what it's aimed at, reading a text, page by page, front to back, quite well (yes the software has, um ... room for improvement, but once you're in
a book and reading ...). So the real question is, are you interested enough in what it does
do, for it to be worthwhile for you. The important thing is that you find something that works for you. These devices are another option, and hopefully there will be more options soon that cover even more of the range of needs.