Can't speak for CBT/ACT, but I think my post about regular therapy [sums it up pretty well](https://www.reddit.com/r/Stutter/comments/18s5q6p/a_lot_of_yall_need_therapy_not_speech_therapy/?ref=share&ref_source=link). TLDR: would highly recommend doing regular therapy, your stutter will likely always be a bad thing in your life so you should work on the things that you actually can control through therapy to increase your overall quality of life.