Here's a snippet from their site:
Recommend it to all of you, it definitely puts the old audio books to shame.GraphicAudio…A Movie in Your Mind consists of full cast dramatization, lively narration, cinematic music and sound effects that create soundscapes drawing the listener into various action adventure series in a variety of genres. All of the GraphicAudio…A Movie in Your Mind titles are created and produced in our Bethesda, MD studios and duplication facility.
http://www.graphicaudio.net/