I'm a big fan of warhammer40k. And I am a big fan of audiobooks.
So I guess it's no surprise that I love w40k audiobooks.
Lately I got my hands on First Heretic and Thousand Sons, both truly amazing!
Audiobooks are pretty expensive but I'm glad I can support this awesome stuff.
Books are great too, but for me nothing beats just closing your eyes in imagination while someone reads the book for you.
If you are not sure if that's your thing, those can be also downloaded free via YT from time to time (significaly less legally) Though it's quite a feat to grab one you like, since copyright police delete them usually week after upload.