I have done 5 or 6 4 weesk cycles of IGF1. I think the most important thing with IGF is to remember that you get what you pay for, i used some cheap igf and some that was 5times the cost of the cheap one. The more expensive 1 blows the cheap stuff away.
I did a some cycles that were 40mcg split bilatraly into muscle just worked and I noticed increased pumps and an increased appetite. No measurable weight/muscle gain or anything else. This was during PCT and im very happy with what i got aout of it because i didnt loose any weight and felt like i was still on something.
I then did cycles that were 200mcg split bilteraly into muscle worked and i experienced extreme vascularity, numbness and tingling in the muscle injected and pumps that made me cut workouts short because i sipmly couldnt extend or contract the muscle anymore. This was during a blast and i deffenetly put on size but i dont know how much can be attributed to the IGF.
I think the low dose cycles are good for PCT and the higher dose is better for muscle gains but i still wouldnt expect to put on any measurable size unless you stack with GH and slin because they work in synergy.
Its worth a try.