My interior is pretty dirty, I can do a review for you on the cleaning tool. I think in a production shop it offers some really nice speed advantages as you can blow out the cracks and crevices while you will lay down a thin film of cleaner. Spray, wipe, done.
I like using pure water in it as the final touch to my interior detail. It quickly knocks out any dust I might have missed, and I like doing a final wipe with a light mist of water.
Overall I think its a very cool tool. I don't think it is necessary to doing a great interior job, but it does offer a speed advantage in some aspects while making sure that everything is done right.