Literally the only definitive difference in anything I've experienced is the liquid consistency of my semen(which may have gone back to normal...I'll make a point of evaluating next time I ejaculate lol). I still wake up with morning wood most every day, my erections are as strong as ever...my libido is definitely not any lower than pre-finasteride. I'm as fit as ever, performing great in workouts both strength and cardio wise, my body fat is still very low.
There was an isolated incident of me feeling abnormally exhausted at the gym, and once in a while I'll feel a throb in my testes, and I'll think "is that the finasteride?" But honestly, there's not enough significance to these things to make me even care of they're related to the finasteride or not.
Then again, I'm only about a month and a half in.
Also too soon to say if it's doing jacksh*t for my hair.