Sony reader has a whitish background which is great for reading in bright light. However at night you would need read under a bright lamp. The width is great and it has that advantage of a slimmer feel.
Kobo Aura as pictured below comes in black or pink. Easier to find when placed with all the other gadgets.
Although the display is a shade darker it is fully compensated by the backlit light.
Although the display is a shade darker it is fully compensated by the backlit light.

