Hmm, I've listened to some audio books before and enjoyed them, particularly is the vocal performance is good. If it's monotonous or the performing reader makes no effort to differentiate between characters, then I lose interest. I have a theatrical background, and I take particular note of that sort of thing, though.
That said, like many people here I prefer reading with my eyes because I can absorb the material very quickly, in blocks rather than word by word. In fact, my tablet can produce an audio double of any ebook on it, and I've been amused by playing around with it in the past because even at the most almost inaudibly advanced speed (which I have read that blind readers often become very adapted to and hear perfectly clearly) my eyes can still absorb the material with greater alacrity.