Edit: I just found a link that includes Kindle Unlimited books with Narration: http://www.amazon.com/b?ie=UTF8&node=9630682011
So yes, if the books you want to listen to are on KU, it's a better deal.
*Full press release embedded here: http://www.businessinsider.com/amazon-unlimited-reading-2014...
Edit: I just found a link that includes Kindle Unlimited books with Narration: http://www.amazon.com/b?ie=UTF8&node=9630682011