I'm in my mid-thirties and won't be able to use tren for much longer. I enjoy the strength/physique changes, sex drive increase, and all the other common positives of being on it. The side effects are still mild for me (although I'm 100% certain that'll change as I continue to age). Mild night sweats, a bit of acid reflux, greasy skin, bright yellow urine, mild insomnia, and a bit of a shorter fuse (which is essentially a non-issue since I'm naturally an extremely patient/easy going guy).
This past cycle I ran 525mg tren ace with 500mg test c per week. Started very low with 200mg tren ace and very slowly worked my way up until I noticed sides, then dropped it back down until the sides were basically non-existent/extremely mild. I'm now off cycle - dropped my test c weekly to 200mg, and getting blood work done again in three weeks while letting my body recover from the damage. The week of getting that blood work, I'm also taking a deload week in the gym. Depending on what the blood work says, I may begin my next cycle to shed what little BF is sitting on my frame.
I'll possibly run a few more cycles of tren throughout the next five years before I call it good. I will say that I do get blood work done frequently (on all compounds but moreso while running tren) and adjust my daily supplement intake as needed. I also keep a very detailed daily log of blood pressure (taken AM and PM), mood, energy, side effects I've noticed, activity changes, etc. The reason I say "possibly" is due to the fact there's a few other milder compounds I think I may prefer to try out to see how my body responds to those. If I enjoy the resulting changes in my physique, I may wind up omitting the tren completely in favor of longevity.