I stuck with my gen 3 kindle -- more memory than future gens, no ads, and the option of audio books (never used it). As technology progresses, I expect more not less. That said, it doesn't have the backlight and using a cover w/ built in light while the significant other tries to sleep? Yeah, no.

I've resorted to using a camping headlamp set on "red" (not as bright/obtrusive) when I want to use the kindle to read. However, I mostly just use my phone and the Kindle app.

Advances in the display beyond the gen 3 (first I bought) didn't merit any sort of upgrade for me.