50-70 dollars? A Kobo Clara is about 100 and has a bigger screen, an adjustable front light and you can easily load DRM free ebooks via USB mass storage or custom firmware like koreader. If you just want to read books you should probably just get a Kobo.
$45 on ali. I've been looking for an affordable open phone-sized e-reader for years, but unfortunately this one doesn't have a backlight which is a hard requirement for me.
The Kobo Clara doesn't fit in my pocket while the X4 does. An e-reader that I actually have on-hand beats one that I leave in a drawer at home so it was an instant purchase for me the moment I saw one.