I'd recommend Gregg to anyone interested in learning authentic Wild Goose (Dayan) Qigong. He is a good instructor. He has good knowledge of Dayan Qigong and TCM and is both calm and patient when he teaches. After spending a couple of years learning with Gregg, he helped me to go to China to learn from his teachers. It was something I'd always dreamed of! . Dayan Qigong is one of the few qigong systems that still carries a lot of depth! It never seizes to amaze me as I continue to explore its movements and teachings!
Adam Gibson (Dayan Qigong Instructor @ Lotus Dao, Lithuania).