What is the best HGH Therapy Clinic in USA?

I am 64 years old generally in Good health,Gymming daily for 40 mins. I am type 2 Diabetic,maintain a good diet etc. Since last year I am totally impotent and now Viagra also does not help much. I have been advised by one Doctor to use Testosterone Gel and HGH injection. The other doctor told me to go in for Testosterone injection . I am a bit confused and scared to try these options.
So I would like the opinions of Good samaritans who have practical experience with any of the above treatment? Does someone try
Utica HGH Therapy? Secondly what precautions and side effects I can expect from this line of action.
Please serious advisors will be appreciated .
Trollers are also welcome