Let me share return of experience using UgooS X3 4GB box.
Firstly I’ve just installed KODI app & test Jellyfish sequences (http://jell.yfish.us)
At first glance all looks fine even in 4K HEVC & HBR.
Secondly Ive installed CE 9.2.4 on USB stick, and results aren’t comparable for the same Jellyfish sequences
Basically using resolution of 3840, all 4K sequences are desynchronised when I asked for the main menu.
Could you test at your side as well ?
Thanks in advance