Speaking from experience, it's total balls. Worse than a gear rattle, comes on harder and isn't that much quicker either unfortunately.
The real bastard is that if you have a decent habit on it, non fent gear won't help much, buprenorphine is practically useless and can even cause precipitated withdrawals even 24 hours after last use, as I found out once. I used it for about 4-6 weeks as it could hammer through 8mg of bupe which seemed great, and as I was buying it from the DNMs, it was super cheap...at first. I'm on methadone now and haven't used in 2 years, but even the thought of fentanyl or buprenorphine puts my stomach in knots.
Good luck buddy, and don't touch it again! Convince others not to either. If noone wants to buy it, it won't get sold, if enough say no way.