I have had DBS for just over 1 year now. After installation of the unit into my chest of course I let it heal properly and did very little exercise with that part of the body for the first six months. Six months later I am back to a full body workout. I recently started the P90 workouts and have had no problem with the unit at all. I will be the first to admit, they could have placed the unit better. It is in an awkward place.