I use a lot of different workouts in my rotations most of the time. I rarely do just one instructor (some exceptions: P90X, or short rotations using 'just Slim Series" or "just Cathe--CTX for example"). I try to pick and choose the best of what each system or instructor offers and mix them together, for example, Cathe for interval cardio and lower body, Tony Horton for Upper body, Tony or Tracey Long for core, etc.