We have finished the Red Workbook (lowercase letters) and Ian is now very proficient in the letters. He is much better in the mirror-image now.
We have not started blue book for he's not good with phonetic sounds.
This material is interesting; however, I have a complaint about this material. It lacks creativity. The games (on the CD-Rom and in the books) are all repetitive. They really could have made it more varied and interactive. For $16 it's ok. I won't pay $70 for this.