I'm still IVing so you can take my advice with a grain of salt... but....
heroin use (not IVing it) was worse for me than IVing buprenorphine. I can understand that's not a common experience for users...
As for tips to quit...
Taper down as comfortably but swiftly as possible, and switch to snorting/smoking your powder/tar, and then get some benzos/Suboxone/Subutex/antihistamines to help out the withdrawal.
For me, I am planning on tapering down to a minuscule amount of buprenorphine (some people may say I am already there lol), and then eventually switch out the buprenorphine for another active ingredient that I have a lot more ability to quit easily.