I have the X4, and I adore it. I wasn't sure if I'd like it or not but got it on sale, and I've been thrilled with it and encouraging folks interested in something more portable than a typical larger e-reader. I just turn it on and read, no need to set a do-not-disturb mode, I just get to focus on that.
"Smaller screen" also sounds bad unless you have flavors of ADHD that cause you to restart the page regularly, and this actually helped me in that regard.
Like, I still have to strip DRM from books I buy if they aren't DRM-free, but I don't buy on the Kindle shop anymore, and most others use Adobe Digital Editions, which is fairly easy to rip using plugins for Calibre.