My current subscription (£7.99) gives me one credit per month. This enables me to download a book which can vary in length from two hours (it has to be quite special to get me to part with my money) to 20 hours.
I've just got my latest credit and have downloaded Meister Eckhart's Living Wisdom: Indestructible Joy and a Path of Letting Go. It's a Sounds True production, which means it will be exceptionally well put together. Before then I've downloaded a Thomas Merton book, a few books by Richard Rohr and before then (2013/14) most of Adyashanti's books.
I don't know how many audiobooks I've got in total -- that's not the point of this post -- but all I would say is that each one has been a joy and helped me to understand so many issues, particularly those connected with my inner journey.
If like me you spend any time driving or commuting, then audiobooks are a must. It's not that you're looking to trance out as you might do with music, but instead to absorb the material slowly and in a way that enables you to go back and listen to any passage that seems particularly meaningful.
Of course, my non-fiction obsession may not be your cup of tea, but despite the fact that I've listened in the past to fiction books on CD and have 2001 A Spece Odyssey downloaded via my Audible membership, I really struggle with stories on audio. I much prefer to read the book (not Kindle).
I know that I could just as easily dispense with my membership but as someone who's innately curious I can't think of a better way to stay plugged in.
PS. Even if you don't want to spend money on audiobooks, you will find a treasure trove of material on Soundcloud that may just float your boat.