Some of the early destroyers had an issue with throwing the strings off on let down, the cam were not cut deep enough to keep them on and their pivoting cable guards were being snapped off when fired do to improper set-up. But again these were earlier models and i haven't heard anything bad about the newer models.
I'm surprised, most people shy away from speed bows, i love speed bows (mine the most lol) but made think about getting one?