I'm taking mast.
My hairline is still good but I'm seeing a bit of thinning between my widows peak and left side of head,.at only 300mg/week.
You've been warned.
BUT... my father had naturally sky high test and he has no hair. All the other males in my family have their hair. He was a freak. Looked like a bodybuilder/power lifter without ever touching a weight, just bucked bales as a high schooerl, and hard farm labor in his early 20s.