That’s a good question. I don’t have personal experience studying with it, but… a) in order to acquire Japanese, you’re going to have to get over the hurdle of the written language at some point anyways, and b) the term ‘spoken language’ has more than one subset, and c) every other textbook series and exposure to Japanese you find (TV, anime, film, youtube) is going to have Japanese text as its visual aid.
That being said, I do think if you pursue learning with this atypical text, then I do recommend getting whatever audio references (cassette/CD/mp3) accompany it. I think it’s designed to have that as a reference.
FYI…
The Speak! series ( Is "Speak Japanese!" beneficial?/Recommendations for casual Japanese )
and the Shadowing series both engage in more listening and conversation. And you’ll probably find a fair amount of high level listening in JLPT books, in addition to whatever immersion you can find on YouTube or Japanese TV or podcasts.