I know I don't want to suppress my DHT. Haven't done exhaustive research but I believe it's important. Raymondo says erections are harder when off, that tells me finasteride has some negative effects on sexuality.
I've been on antidepressants for 25 years and some have said they experienced permanent sexual dysfunction after only a few months. I know my "anorgasmia" resolves itself in 2-3 days if I stop my meds so in my case the system bounces back quickly. Finasteride seems the same, some claim long term sides.
That's a valid concern and I thought about it a lot. I honestly thought erections were so painful off finasteride for the first few weeks because of some overcompensating effect. After that it seemed to stabilise, although I've never stayed off for more than a couple of months.
My girlfriend constantly tells me that I am hard as a rock and way too big for her and to take it easy. So, normal strong erections when on, it's just that when off it feels like the dick is about to explode, crazy morning wood, etc. Now in my late thirties, I also get erections just by watching her walk, we even have a joke about it ("but I was just walking across the room!")
Been on an SSRI for a few years now, imo it has had a far greater impact on my sexual health than the finasteride. Very difficult to cum, although she loves it. After quitting my first SSRI fifteen years ago ago I entered such a terrible withdrawal-induced depression I didn't have sex or an erection for six months.
The stuff about DHT being an important neurosteroid gave me pause a few years back, I never looked into it deeply, too scared. I know of Dr Hasson in Canada, an esteemed HT surgeon who has been on it ever since it came out and has fathered children, he is pro-finasteride even though he has every incentive to be against it.