So sorry you're going through this.
My first detox was on methadone -- I was in a thirty day program, and the dosage dimished rapidly. I was probably only taking it for about 12 days. What I remember most is that I couldn't wait to get to the nurses station for my little orange cup of "medicine." Granted, my heroin habit wasn't that bad when I checked into detox -- but the methadone worked well, and I don't even remember having any withdrawal. I was extremely uncomfortable emotionally though...and I started using again within a week of my release. Simply treating the body doesn't treat the mind. When I had to go back into detox again, I was surrounded by people who were using methadone, either as maintenance or to kick -- and they were above and beyond having a harder time than those of us who were just kicking dope. While the mental anguish was likely equal, the physical pain was overwhellming for them. Especially for those who'd been on methadone for an extended period of time. Methadone IS evil, I agree -- it wasn't designed for detox, it was designed to keep junkies junkies. Take away their voice and reduce them to zombies dependent on the system as well as the drug.
I'm a pretty solid believer in a medical detox; I've written here before, but I kicked using ativan, robaxin, decreasing doses of Norco, clonopin and clonodine. And while it wasn't great, it didn't suck too horribly either. But once the detox was through, I started working through the other things that come with addiction -- the psychological stuff. And if I hadn't, I would still be getting high. It's not that difficult to stop, if you've made that decision -- but it's hard to stay stopped.
Best of luck,
GRD