I am on TRT.
I have been for a few years now. I went to several endos, GPs, etc. and eventually was able to begin injections. I do not trust doctors whatsoever. Everything they told me was a waste of time, and every avenue they went down was a waste of resources, until the end result: once a week injections, 120~ mg test cyp a week.
The reason for my low T is unknown. I do not wish to go into it because nobody figured it out. I also have to take thyroid supplements. My hormones have been a disaster since I was born. I was having severe migraines until I fixed my thyroid, also. Now I weigh 100 pounds more than I did 5 years ago (healthy weight). There was a lot going on.
Now, back to TRT... The reason I say all 5 or 6 of my doctors wasted my time is because I knew what regimen I needed before my first doctor's visit. I went because of general lethargy, apathy, and erectile dysfunction. Also, I took the supplement DHEA (purchased at local drugstore) and it made me feel like I was on this incredible, euphoric high. I had never experienced it before, and it didn't feel like a drug. It felt natural, like this was what life was supposed to feel like. I even grew a mustache because of it. Sadly, it stopped working, but I went and got my bloodwork done, etc. and had low T.
But I do say that the doctors were a waste of time because they all have f*cked me around, and one of them I'm almost positive was just trying to get me to keep coming back, because he was trying to get me to do 400 mg of test every two weeks, when the half-life ensures that it will be completely gone by the 2nd week no matter how much you put in... He apparently didn't know what a "half-life" was, and was "confused" when I would come back every two weeks and there was "no change"(because it was all gone by then)... Made me come to do my own injections in the office, each injection cost $40 when the whole bottle costs $40 if he had let me do it myself...They said "money wasn't important to them;" well, it's pretty important to me. Every doctor was a quack. It was a pain in the ass. None of my doctors thought TRT patients need to monitor their estrogen, either, even when I went in with symptoms of elevated estrogen (itchy nipples, symptoms of high blood pressure, sweating profusely during the night). I literally knew what I needed to do before I started that long 2 years of doctor's visits... it just took 2 years of "trial-and-error" (mostly error on the doctors' part) for me to get there.
Now, for what TRT does. It's hard to say exactly, but my life has changed significantly (maybe because it took so long to get it dialed in, that my life in general passed me by). But I am a completely different person than I was when I was younger. Conversations are smoother and I feel like I have "energy" to use and expend at my command, would be the only difference I can note.
Except for one other major difference - my sex drive. There are distinct differences between how I feel when I inject 60mg, and when I inject 120 mg.
60 mg has me wanting to study and use my brain.
120 mg has me wanting to lay down in a hotel room and take dick from as many guys as I can (read my other topics where I tell the stories of my doing this).
It's all very subtle. There's never a moment where you think "I can feel the testosterone!" or "The testosterone is causing this." It's all happening naturally, and really takes concentration to pick up on the coinciding events down the timeline.
EDIT: Okay, I will say one more thing... I did do steroids one time because as I am injecting for TRT already, I might as well go a step further. I injected 600mg a week, and used aromatase inhibitors (which block production of estrogen). I don't really remember those weeks, but I was basically on auto-pilot. I didn't feel very many emotions, although I did get fairly angry twice (didn't blow up, but really stood up for myself when I needed to). I would not say quality of life was necessarily enhanced - it was just different. My veins on my biceps basically stuck out of the skin, and you can still see them. My nurses have always told me I have hard veins to find, but ever since I did that steroid cycle, I have gotten comments saying I have "easy veins."
I also had bad acne on my shoulders and back after I stopped. It's normal for that to happen, but it bothered me enough to where I got on accutane to get rid of it. Being on accutane is a nightmare, but it really works to clear up acne.
One more thing - when I was on the cycle, my dick would be rock solid just from a gust of wind. I was incredibly horny, and did not want to bottom at all (I wonder if estrogen has anything to do with that, because normally I like to bottom when I'm taking TRT dose, but on steroids I wanted to top everyone).
My dick was not hard just walking around, but anytime I needed it, or even thought I might need it, it was suddenly there sticking out of my trousers. I will be honest - I topped at least 20 guys during my steroid cycle. I went to my friend's in the city and he said it was going to be a while, so I found a bottom before he got home. I found another bottom later that night, and another on the way home the next day. I would go on breaks at work and top guys in the surrounding areas. Professionals would be in hotel rooms and invite me over and I would be hard before my clothes even came off. I remember one guy told me, "I liked seeing you hard as you walked through the door."
Sometimes my sex drive can be a problem. There are days where I wish I didn't have such an overwhelming desire to have sex, but I kind of like it. I didn't have any sex drive at all growing up. I wonder how mine compares to guys that have theirs "naturally." But any time I want to tone it down, I just lower the dose.