I've read a lot about Dr. Cooper and reviews seem mixed. However, my experience is that speech therapy can work. It worked for me. I have AB quite severely; I was largely unable to communicate verbally. It was hard work and took time, but I learned alternative phonation via speech therapy (some folks call this reprogramming the speech mechanism, I usually call it my "engineered voice") that enabled me to return to work and social life with a highly functional voice. Producing the voice takes effort, and it isn't perfect and I often use amplification, but I'm very happy with my result. While I stopped therapy two years ago, my voice has not reverted. In fact, my abilities have continued to improve over time.