Just a few hours use, I feel I like Kindle eReader more than Koko.
1) Page flip over is faster
2) Sleep mode has wonderful pictures as screen saver.
3) Chinese support is OK.
4) Built-in MP3 player.
I use it as background music.
5) Quick open the book or document
6) Online document converting service
7) WiFi, it is helpful for download the document which send to Amazon for converting.
8) Color is wonderful, good for adult.
The color of Kobo is good for kids or children.
Oh, almost forget the Text to speech. It can read the book.