I use a Kindle Oasis and love it.

I’ve seen the Xteink devices mentioned here and am intrigued, but the screenshots turn me off instantly. The font rendering or hyphenation or kerning (not sure exactly what) looked terrible.

Fortunately, since these run open source software, this will likely eventually be fixed. The Kindles weren’t great at the start either, so I have a lot of hope for future versions of the Xteink devices.