The content is good although too much space is given to testimonials, and more space should be given to explanation and theory.
The CD is very well laid out with instructions from the author, a singer demonstrating the exercises and the exercises themselves laid out on different tracks, which make it easy to skip to the essential bits. You can practice while driving for example.
I have been getting speech singing vocal training for over a year. Unless you are already a well trained singer with good technique, you should not use this type of course without also getting lessons. A vocal coach can identify how to improve tone, breathing etc and point out technique errors. It is so easy to damage your voice by using incorrect technique or overdoing the exercises.
After using this for a few days and then applying the technique to sing along to a recording, I was able to do so without straining and hitting higher notes than usual with much less effort, which was amazing. I feel that I am now on my way to a voice that I did not dare to dream was possible.
The principles behind this book involve using exercises which educate you to sing without the larynx rising up which actually interferes with good singing, and to sing with a connected voice from chest voice into head voice, without breaking into falsetto.
The second CD is more about applying the exercises and producing the speech level singing tone, and runs through song examples using those passage areas with very useful tips to avoid splattering the sound. This is a great investment, which I highly recommend.