I was looking into an e reader about 18 months ago, I looked at the kindle and that type of product but the size was what turned me off them. I bought an acer tablet pc form eBay, one with the flip over screen, this was very good and served it's purpose but was extremely heavy to be used like a book and the battery life was only a couple of hours.
I eventually settled on an iPad for a number of reasons,
1. Lightweight
2. Colour screen, decent size too.
3. Allowed pdf's
4. More vesatile, Internet, video, music etc
5. Large capacity memory
But much more expensive.
Also recently, look at a thread for me here, I bought a 7" my tab. This is as versatile as the iPad but the clarity of pdf's is a little poor due to the screen size I feel.
Good luck
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