Also, it's not true that the enTourage store has closed. They took down the accessories page, and are not now selling their devices direct, but they still sell ebooks, textbooks, apps (mostly free), and music. The apps are download-to-your-eDGe only, but the books can be purchased by anyone (pdf and epub)!
Which of your devices do you read on? I have (and love) a Sony PRS-900 but find myself reading on my Pocket eDGe because I can look things up in more ways while I read, and take time out to make a note or play a game of solitaire or browse the internet if my interest in the book I'm reading lags.
I have yet to install Ermine, and 2 months down the road I am still learning how to use my eDGe, but it has successfully wormed its way into my life.
Let us know what you decide!