S.R.
I don't PERSONALLY have any experience with the Amazon publishing, but I know of someone who does. She's done one book with them and loved it so much she's doing her next one with them too. (She's a fiction writer. Can't wait for her next book!) Anyway, this is the link to her facebook "author" page. You could see if she'd be willing to tell you about her experience. I don't personally know her, but (I just checked when I saw your location) and she is currently based out of Chicago as well! Anyway, here's the link, I bet she'd be more than happy to give you some info!
https://www.facebook.com/greferauthor/info