I'm interested in this as well. I'm on the verge of beginning IR training and looking into possible study options. While I feel it would ease training with visualizations offered in the DVDs ... is it worth $200-$300, esp. if I can in turn give that money to my CFII to help visualize for me, I do have to fly with him anyhow.
For what it's worth, I read on another thread or board ... some felt the Sporty's work better for the checkride, while King's better prepares you for the written. Not sure if anyone else would buy off on that or not ... just what I've heard.