Thanks, everyone for participating.
I got the Onyx Boox Nova (the one without the stylus).
Overall I am happy with the device. The screen on the Nova is better than the Likebook Mars. The software is better too. There are areas that the Likebook Mars is better, e.g. using Mars's keyboard is faster and smoother.
One problem I noticed with neoreader is that the highlighting functionality in PDF documents isn't consistently accurate. Also, highlighting becomes unusable if you select the underline option.
I installed KOReader - both stable and nightly versions - but noticed the screen flickers when you select a menu or highlight texts. It is really annoying - does anyone else have this problem?