DAF devices have been deemed unethical by many. I don’t think I’ve heard of any success stories with DAF devices. I study speech and language in college, the brain is a pattern recognition machine. The device may seem beneficial in the beginning but once the brain catches on and realizes what is happening it will no longer work. At least, that’s what I’ve been taught in my classes. However, please note that I am EXTREMELY BIASED. I had a speech easy device and it worked for 2 weeks before it stopped being beneficial to me. Again, I am extremely biased. I am no longer seeking fluency and I just stutter freely and love to educate people on what stuttering is. TLDR Not worth the massive amount of money but I am biased in my opinion.