The most popular choice currently appears to be the Onyx Boox Note:
wiki.mobileread.com/wiki/Onyx_Boox_Note
mobileread.com/forums/showthread.php?t=293789
The second best choice might be the Boyue Likebook Note:
wiki.mobileread.com/wiki/BOYUE_Likebook_Note
mobileread.com/forums/showthread.php?t=295859
If a much faster CPU, double amount of RAM, somewhat less buggy and more complete software than the Likebook, and a very dependable European dealer is preferred, than the Boox Note might be the better choice.
As it completely depends on your own requirements, compare and decide yourself. In my not so humble opinion, none of the available 10 inch e-reader devices are really recommendable, as the included software usually is a disaster across the board, regardless of the Android version.
Based on my very personal own criteria, i favoured the Likebook Note over the Boox Note, as it has an SD card slot, function buttons, and is quite a bit cheaper. So far it has proven to be fast enough for my PDF reading needs (i don't do the usual ebook formats), despite the rather unfinished and incomplete default applications it comes with. Installation of Librera, RelaunchX, and Goldendict slightly remedied most of the software pains.