Just to let you know there are many similar devices sold for $57 on geeks.com:
I didn't buy them because I felt the screen is not that much different from the Sony PRS-505 reader I have now!
I ended up buying a jetbook, which I'm very happy with, despite the lower resolution. For text, it's just as good as an e-ink. For PDF, just as bad.
My next e-ink device will have to be a 9" device!