I have/had one. My parents bought me one when i was a senior in high school—probably when i was the darkest place I’ve ever been. I wore it for a few weeks. But, honestly, it’s annoying as hell. The pain of not being able to hear what others are saying, or being so distracted at this little altered noise in your ear, was worse than he pain of stuttering. I changed my views and outlook slowly after that. Acceptance was easier than fluency through that device. The device itself made me stutter less, but i think it was just because it slows you down. Slower pace always makes me stutter less. But again, the cost isn’t worth it. And, getting to a natural sounding speech with it a as impossible.