For me, I already have some nice large computer monitors, and a nice laptop, so if I want to read on a phosphorescing screen, I'm covered. No interest in an iPad, and I already have a 10.1" IPS Android tablet for an even more portable eyeball-electroluminescing experience. But what I really want is an experience more like reading on paper.
Just acquired a Kobo Aura HD for $80 - it's at least largish (6.8") and has a microsd card slot so I can carry 32Gb of pdfs. I've been reading pdf books and scientific papers on it and it's not a bad experience at all.
(I don't get the recommendations for non-eink tablets [I've just had one on
my 'welcome thread' too; now closed, so I can't reply.
I've spent the last four years trying to use a non-eink tablet for pdf consumption and it's not a pleasant experience for me at all, and so I just don't end up using it.)