Most people who have been on high doses on benzos for long periods of time have some horror stories. Mine included a cold turkey attempt from 8 mg of Xanax per day, atlhough I've come off higher doses, but the 8 mg in June of 2010 was the worst thing I've ever experienced.
It's vitally important to be working with a doctor or at the very least, a nurse practitioner on this. Some people don't experience withdrawal symptoms, others get absolutely brutal symptoms. No way to predict but the longer you are on, and the higher the dose, the more likely you'll have severe symptoms.