I've used androgel for over a year now.
If you think you have low testosterone, you can get a test for $60 at
www.salivatest.com
I've also used a cream from a compounding pharmacy. I'm using androgel because my insurance pays for it-the cream is a better deal IMHO.
Anyhow if you want to do this, find a _good_ anti-aging doc. There are lots at
www.acam.org.
Another hormone level to check is HGH.
I wouldn't do it unless you think your T level is below what has been optimal for you.
Also if you decide to start taking T: consider banking some sperm in case you want kids later(T supplements cause you to stop producing as many sperm unless you cycle carefully-this effect is usually reversable-but it is a pain in the rear to do).
Good luck.