Barb: I'm sure Dave will weigh in on this since he's a wealth of info on both! In the meantime, I suggest your BF try whatever they are recommending.
Methadone (as I understand it) is good for long term, heavy opiate addiction or people with chronic pain.
Suboxone is for moderate opiate addiction (if there really is such a thing?). The withdrawl from methadone is really, really hard. The withdrawl from suboxone is also hard but alot of people do it by following a tapering regimen. Which he should follow.
With Methadone you have to get in a program. He has to prove himself before he'll be given methadone to take home and even then it will only be a few days worth. I know people who eventually got off methadone -- but it took them years to do it. Keep in mind: both my friends had been addicted to heroin for 20 or more years so they were willing to invest the time to get off for good.
Unless he's been addicted to OC's for many years, he's probably better off with the suboxone.
Keep us posted! Good Luck,
YM