Re: All my life
+1 for e-ink. Suitable in all outdoor use scenarios.
And forget about colour. For most real use cases I struggle to see why colour is essential. Nice yes, essential no. (And perhaps it would make some strategy boutique *onks consider what their "work" looks like printed in black and white on the office laser.
Ok, 1f you're going off into the wide blue yonder and putting some maps on the thing, I agree colour would be more than nice.