I ordered both actually, because I couldn't choose.

I'm not sure if the Book Jacket allows access to the hub connection port or the on/off switch. I've put an email to the M-edge guys for the answer, but given the access on the Sleeve, I should think the Book Jacket would allow power switch access. It'd be a major pain to have to remove the iLiad from the Jacket everytime you need to turn it on/off.