Referring the OP to a thread about an aggressive dog whose mother was aggressive and litter mate had issues it probably not a great example.
OP - what are you looking for in a dog? Are you looking for an active dog? Are you willing to put the time into to training? GSDs come in many 'flavors'. The puppies are known as landsharks and need alot of redirection. If you talk to a reputable breeder many of your questions will be answered.
~The strength of one's opinion should not exceed their knowledge on the matter~