as always, no one here advocates touching anything hormonal till you've reached your genetic potential naturally through proper diet, training, etc.
At any rate, IGF-1 seems to be working well for most folks, and it is highly unlikely that you would not respond to it. I'm told that there are some who are non-responders, but these cases are extremely rare.
Do some more research before jumping into something like this...definitely not something to take lightly.