You can read about
the pros & cons of electronic devices like SpeechEasy on http://www.
nidcd.nih.gov/health/voice/pages/stutter.aspx. There are no long-term scientific studies yet to show consistent efficacy in "real world" situations. They are very expensive & require a great deal of conditioning. Commercially, they are not marketed as a cure. There are more testimonials than scientific proof at this time.