Generics vs Brand for Drugs like Finasteride

I hear some people say that brand name worked better for them and then I also hear other people say that it doesn’t matter what brand you use…

It works because the FDA requires comparable testing for generic drugs. Some companies may not comply. If caught without compliance, they may never return to the market. FDA calls the consequences. I suspect that if you purchase a generic from a standard known pharmacy, it will likely be certifiable.