Spironolactone is a blood pressure medicine that is also an anti androgen. It not only blocks, it also reduces testosterone levels. It makes no sense why you would worry about a little finesteride but take that instead. Especially when reducing DHT levels is going to have the greatest effect on hair loss.
I think the finesteride horror stories are overblown. I haven't been able to find an explanation as to why people would be suffering permanent dysfunction upon discontinuation. Unless SHBG levels don't go back down in response to increased DHT. Probably the people who are having problems were older, going through andropause, had some arteriosclerosis and reducing DHT was the final straw that made their low testosterone levels obvious.