Finpecia questions

[Dav7]

Just curious if anybody could help me out with this. Regarding Propecia, I may have to give it the boot for the next few months until I'm back on track money-wise. However, I don't want to drop finasteride for that long and have been looking into Finpecia. So I was wondering,

(a) Is it as effective as Propecia?

(b) What percentage of DHT has it been proven to block, and how close is it to Propecia regarding DHT blockage?

(c) Can you be 100% sure that you are getting it legit if you get it through a pharmacy on prescription?

(d) Will it have long term effects regarding switching back to propecia, e.g. shedding, making propecia less effective etc.