Link to October 18 morebookreviews.com post, "Audio Books and Recorded Books: Do You Know The Answers To These Questions".
As for my answer to the question, "Is there a difference between having the author of the physical book tell the audio version, or is it better to have a professional narrator do the job?"
Absolutely, positively yes.
The only author-read audiobook I managed to finish was Myla Goldberg's The Bee Season. Toni Morrison, reading Beloved, put me to sleep. Richard Russo, reading his short stories, made me roll my eyes.
My nomination for the best recorded-book performance ever: A Confederacy of Dunces, featuring Barrett Whitener's tour de force.