The only way to tell ... is to get a lab test done to measure IGF.
Example:
Cycle for a month 2 units per day for 5 days and at the end of the month evaluate the IGF levels (compare with before cycle levels).
If you see marked elevations ... than you got some legit GH.
I can say this.
When you are on ... no matter which brand ... you will grow.
Your hair will grow, but not the areas already bald.
Nails too ... you will need to cut them 2 times a week.