I'm gonna chime in with some of the others and say Onyx is actually really good. I got my Nova 3 (black and white, not color) to replace an old Kindle and I've been loving it. The fact that I can write notes on it has been a game changer for me and has completely replaced pen and paper notes. On top of that, the fact that it's Android means I can install other apps and that just opened all kinds of windows for experimenting with the device that I didn't expect, it really is just basically a tablet with a much more readable screen. And second best thing to notes I've found about my Nova is how nice reading manga is on it, I'm even paying for a subscription to Shonen Jump now plus using Tachiyomi for fan-scans.
Only damage the thing has taken in the time I've had it is a couple corners coming off the case, which I just glued back on. Device itself feels good as ever.