I think the software that you use to read ebooks with is a major consideration (most is free) if using a laptop.
I used to read in bed on my laptop using a wireless presentation thing to turn pages (about $10) and it was ok esp if the screen was not right next to my face
Reading software should fill the whole screen when maximized on PC as it seems to me easier on eyes and less distracting.
Ereader is more comfy although not as easy to see in low lighting. Plus you can take it on the plane, bus, waiting rooms etc.