I’ve used both dedicated eReading Devices and Multi-function devices and if I had a dedicated eReading device that had a backlight, I would use that one probably exclusively. Dedicated eReaders are those devices whose primary function is to serve as an ebook reader. Most dedicated devices also have an mp3 player, but for the most part, the dedicated device is meant for just one thing: reading.
There are dedicated e-readers in every price range with the least expensive being the eBookwise and the most expensive being the Iliad.
Ebookwise

First up is the $100 device. The most cost effective ereading device on the market is the eBookwise. The eBookwise can be purchased via the eBookwise store (a division of Fictionwise) starting at $109.95. eBookwise also sells two bundled packages: an ereader with a 64 MB Smartmedia card and an ereader with a 128 MB Smartmedia card.
According to eBookwise, the typical number of ebooks per device is as follows:
Approximate number of typical eBooks that can be held on the eBookwise-1150 with various memory options:
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