I was wondering if some guys who have been on TRT a long time can chime in.  I’m 42 and working hard to keep my testosterone up.  Lost one testicle and had chemo so it isn’t easy but I’m tired lots. I finally got it back up to 450 but I’m still tired.
Anyway, I was just wondering because I read a lot of posts about how people feel great after they start it but then after six months to a year, they seem to go back to getting tired or low libido etc. So I was just curious if I got started on it I would probably be on it for the rest of my life and I was wondering how manageable it is and does it keep helping 5 to 10 years out.  Or do you start feeling like you did before you even started but now you have to be on it because your testicles don’t produce any T anymore?  I would love to hear from you guys have been on it five or more years and what it’s like. The more honest the better. I really appreciate your time and thank you so much.
		
		
	 
Been on TRT for over 13 years, worked great since the first injection.   I first noticed symptoms ~age 40 but didn't start until age 57.   I really have had no issues since I started,  though it maybe difficult to duplicate what I am doing.  Once 7 years ago I stopped and my T levels went back to about the same at ~350.   Only stopped to increase sperm count.
Using clomid (7 years ago) I could get T up to 470 ng/dl.  Didn't help with symptoms, but at that time I was looking to increase fertility, which did increase enough. 
1st question, do you care about fertility, having children, if that is not a concern it makes it simpler. 
IM / guess in 90% of situations, lifestyle changes won't help enough. 
As far as being a life long commitment, IMO the forums make too big a deal about that, for the majority of men you can go back, just that your symptoms will return, and since X amount of time has passed, your levels maybe worse just because of age. 
2nd. Before starting, I would get an iron panel, and make sure you know your HDL/LDL levels, test for shbg.   Those can change after you start, and knowing SHBG helps with understanding your free T levels. My SHBG moves around, but it's usually 45, though if I increase T a lot, shbg also goes up, and some supplements seen to increase SHBG.
I started with Nebido (testosterone undecanoate) which I initially got while visiting Thailand.  It was very easy at that time,  my age (57) and symptoms were enough, the doc did a psa and EKG test.  (guess the doc was more concerned about cancer or heart attacks)  I had various means of getting Nebido, basically importing it using a script I got.   Now I just get generic testosterone undecanoate, (cernos depot) which is ~$120 per year.
I use this because it's the lowest cost/hassle.  I inject once every 10-12 weeks, this protocol also greatly helps to avoids any HCT problems, mine rose 43>47 (37-51).
Biggest problems,  being able to consistently import this and it's harder to inject (4 ml) into glutes.  PSA did go up, but it was higher than average when I started.  PSA had been 2.1 at age 40 before TRT, for 8 years on TRT it stayed in range 2,1-2.8, the last 5 years it has been 4-5-6, but that is because my prostate is enlarged ~70 ml, no symptoms but a larger prostate puts out more PSA. 
~6 years ago I joined 
Defy, a T clinic. For me, it's more of a backup just in case.  There I used both creams and testosterone cypionate, tried HCG, thyroid meds, metformin, mostly just curious, I don't have issues that need those types of meds.
My motivation levels did go down the last 2 yrs, but then again, I am 70 now, and I think its more psychological  than hormonal.  It's far worse if I were to quit TRT.
If I had to quit T-undecanoate, I would go with testosterone cypionate.  Creams are OK, don't like everyday and they are a bit more messy, though with T-C I would likely inject every 2-3 days.
Positives, huge increase in energy, loss of 40 lbs, huge increase in libido.   No negatives, just another thing I need to do now which I didn't need when I was younger.  (here is kind of a negative, you are out of sync with your spouse/ friends.  More libido than spouse, more active than similar aged friends)
I don't use insurance and I am not under a doctors care for TRT, which for me is a positive.  If I were using a clinic, I would have to test every 3-4 months, do a lot more paperwork, get my urologist to OK it since my PSA > 4.0.  If I were to want to use insurance, I would have to jump through hoops, get my levels down low enough to qualify, and it wouldnt save me money. it's probably more expensive.