Super potent stuff. Keep in mind that when most people say they gained 20-30 pounds with it on their 1st cycle, they are usually referring to a 3-4 week cycle...not 8-12 weeks. I don't know anyone who has ever put on 30 pounds in 3-4 weeks with injectables alone...1st cycle or not.
Still, I hear your point--a 1st cycle isn't really a reliable example of potential gains for experienced users. Fortunately, 10,000's of people have used it when it was legal, so we know exactly what it does. It is the strongest steroid I have ever used. It was also absolutely horrible in terms of side effects...the worst ever...by far...and I am someone who feels fine when using pretty much every steroid, including SD. Most of those who have used it share a similar sentiment.
Tons of water retention...more than any other steroid I have ever used. It is the only steroid I have ever used that gave me blood pressure problems. I can use tren, Anadrol, SD...anything really...and by BP goes up maybe a few points at the most. The first time I used M1T my BP rose from 120/80 (roughly) to 100/160 in 10 days. I experienced horrible appetite suppression, intense lethargy, and even serious depression. I gained about 20 pounds in 3 weeks at 20 mg/day...and I was NOT able to eat as much as I should have been. Strength gains were rapid and impressive.
It pretty much kicks the shit out of every other AAS out there in terms of mass gains, especially on a mg per mg basis. Even at just 20 mg/day, it is stronger than Anadrol at 100 mg/day. When comparing overall mass gains, it is stronger than SD, but because so much of the gains are water (I.M. and sub-q), I would say it is only slightly stronger in terms of actual muscle fiber growth. But...if you ever want to put on a ton of mass quickly, this stuff will get the job done. I will probably never use it again. I felt so bad on it that I just have no desire...not to mention that it is the most liver toxic steroid out there, mg per mg (aside from methyltrienolone).