Welcome to MobileRead!
I don't know if an eDGe is exactly what you want. You cannot type on the eink side out of the box. You might get what you want using Javese's lcd2eink program (not sure, I haven't installed it yet

), but even if lcd2eink gives the effect you want it will require the use of the lcd to some extent.
Of course you can just get one and enjoy it, even if it isn't your perfect solution.