Love this reader. Tons of customization  decent text rendering and the support of Mobi-book format. The only thing negative I see so far is the slow opening  especially by ePubs: sometimes it took 10-20 secs just to open a book! If you can fix this  it would be perfect! The default view of the library is also confusing and not helpful. Better change the default view to show all books in bigger cover thumbnail. If you have under 100 books on your device  I think browsing all is the best way to navigate.
March 14 2017