I've been to 2 trainings with Mckenna-Breen.
They have the latest technologies in NLP as they train with Richard Bandler.
I never listened to this audio program, but the ones I have of them are good and full of useful distinctions on the topic.
If you want the skills, I'd say go to a live training, it's much better to really acquire skills.
Richard Bandler is giving some in the U.S www.purenlp.com or I can give you other names of trainers I experienced and got mesurable skills.
My opinion!
Alex