I used a generic finasteride for about 1 and 1/2 years. In my case, I did have noticeable changes in facial hair. Not in the amount of, but in the speed at which it grew. Different now that I stopped using it, back to normal.
I also experienced (as my wife noticed first) a fair bit of re-growth of head hair. However, it never grew longer than 1/2 inch, and it, too ceased when I quit the finasteride. BUT, I was also using Premarin at that time, so those results may have been skewed. Fortunately, having started to lose hair at the age of 18, I've had plenty of time to become accustomed to it's departure. As with anything, the effects of finasteride may depend on the dosage. I wasn't exactly hoarding it.
PM has not yet negatively interacted with my BP meds, or anything else I take. The only note I could make, would be that the larger the dose I take, the more difficult it is to keep from adding pounds. Hopefully, with the arrival of warmer weather, more outdoor time, and the exercise that goes with that, I may find that I cannot even blame weight gain on PM. Take care, all. Patti