It helps with my Japanese a lot and actually reflects what I learn in Minna no Nihongo textbook in class.
If you're just beginning to learn Japanese, consider this book!
Be careful and pay attention to the other reviews. The translations aren't perfect but that's not how I use the book. The women's voice is over exaggerated as well. But, for my purpose the book is sound. (And that's just to develop a nice rhythm as I talk in Japanese.)
I have only done 8 out of 900 sentences and I can already see an improvement. It only takes 10 minutes per day so it's hard to burnout using this method. I think it makes a great addition to my self study regime which includes Human Japanese, Genki I & II decks on Anki and Michel Thomas methodology on audio.