[Mono]

Well, I have LCD screen, highquality screen tablet and e-ink M92. Each of them has advantages and disadvantages. I use all 3 heavilly. Each one for what it was designed for. Up to date there is not an ideal all-purpose gadget available. It will be when e-ink will be capable of at least 65k color shades, and the speed of refreshment will rise a bit and it will be posslible to roll the screen (the device). It is only a question of time.

For reading & scribling in text M92 wins. Highend tablet might be good solution if scribling is not needed or just from time to time... 12+ hour usage might be enought if you can charge every day, but it is not always possible. And it is also more comfortable to charge only time from time.

EDIT:
Samsung Galaxy Note 10.1. - might be option if one needs scribling and does not mind LCD screen. To be honest, I am not sure if e-ink has advantage (eystrain - wise) over good LCD tablet for indoor use. Outside, if there is lot of sun, e-ink wins by its nature.