I was on sertraline until just over a month ago, had an absolute nightmare with it, made my anxiety ten times worse and it killed my libido. When I wanted to, I could get hard, but it took me an age to cum and there was zero sensation whatsoever.
After coming off that I was put on mirtazapine, my libido was zero on it again, but I had no problem performing as normal when I wanted to. However, I came off it through my own volition as it's a sedative, I couldn't wake up on it and it made me feel completely braindead. I'm inclined to agree with the poster who said they're a scam after trying them myself. Hopefully CBT will work for me.