From what I've heard, Methadone is the devil. Stay away from that shit at all costs.
Suboxone is a much better route, however, I agree with Captain Quantum, the best way to quit is cold turkey with out the use of the aforementioned medicines.
Try and go cold turkey, and I mean REALLY try. If you can't do it, make an appointment with your doc and inquire about suboxone. A lot of times they will put you on a 5 week schedule or something, allowing you to kick the habit with the least amount of pain. I do not know any of this from experience, so my information may be a little off.
Good luck!