I use it. My doctor wrote me a script 2 years ago. Its for 5mg finasteride tablets. I break them up into thirds and take two a week. Basically, I'm taking 1.67mg twice a week.
It works, no doubt about it. I haven't got the sides that some people experience. I am on TRT so I can't tell if my sex drive has decreased. Nothing noticeable anyways.
Just remember it is a commitment. It will regrow hair but once you stop the medication, the hair that has been saved or regrown will fall out just as if you never took the drug in the first place.