By full sun, text black on white, I still don't have to put my glasses on. I wouldn't throw away such a moment for mowing the grass. Besides, I personally hate mowing the grass. Let it grow!
Our eyes differ. Back in CRT times some of my colleagues were quite comfortable with 60Hz. For me it was a torture. I needed at least 75Hz not to see the monitor flicker, something to do with eye accommodation I suppose. LCD technology helped - but still: the geometries I'm complementing every day on LCD monitor has many colors and intensities and it's ok. When I start to read - white (no matter white on black or black on white) is too bright after more then ~35 minutes. Dimming doesn't help: it just dims the picture which is not what I want.
Many of my train journeys last more then 6 hours and there is seldom opportunity to recharge.
So I'm for e-ink. Be happy with your smartphones/tablets as long as you can but in the long run, for the
most (IMHO) of us, it is either e-ink or dead tree or change of interests.
My PRS-T1 is trying to die on me and I don't see worthy replacement yet. Kindle is for me too restricted.