The fine is half-way understandable (they have been responsible for an awful lot of piracy, after all), but the prison sentence is over the top. I usually think of prison as being used to hold physically dangerous individuals (murderers, rapists etc), and frankly, i don't think that those four guys are any more dangerous than your average bloke. (I'm neutral about all this, mind you)
Besides, taking out the founders of any organization doesn't guarantee it being shut down.