After having had a bunch of formatting issues with the XTEINK X4 for EPUB files, I decided to give the crosspoint-reader a try. My god I should have done that right from the get-go. The OS feels a lot faster and it has no problems when displaying EPUB files. Yes the official OS is mainly intended to be used with a specific file format, but since I am lazy the crosspoint-reader with its better EPUB display capability is the simpler solution. The installation was straightforward and the user guide was very instructive as well. For customization, information and other helpful links there is also the community website at readme.club.