Well the only evidence I have personally seen is the improvement of my wife's pronunciation. She doesn't mispronounce the words she practised anymore. Also I

Well the only evidence I have personally seen is the improvement of my wife's pronunciation. She doesn't mispronounce the words she practised anymore. Also I got positive feedback from the early beta users (other students & English learners) so I assumed it was useful in its initial state. But yes, I will add additional information with benefits and comparison with other products. Thanks!