I am very happy with M92. But don't flash the new 1.7 firmware. It changed the way viewing PDFs. 1.6 firmware is good enough. I use FBReader for my "Preferred Applications" reading epub/doc. It's easy for me to change the fonts. You can copy all the fonts you like from Windows into "fonts" folder.
The device is very good, except the pen/stylus ( like a thin stick )