Just thought I'd add that Pennhip can be done at 16 weeks and is probably better than OFA anyhow (gives a more extensive look at the hip joint).
What do you expect this dog to do if someone drives down your driveway and gets out? Do you want him to just bark? Bark very aggressively, lunge, possibly bite? Or do you want a sure bite? A German shepherd should do more than just alert you, he should be either 2 or 3 of the 3 options.
You can teach a dog something without him being obedient lol. Say Dog A and Dog B both know come, but Dog A
really, really, REALLY likes to chase squirrels, and Dog B kinda sort does. Well, you're going to have to put a whole lot more effort into getting Dog A to come reliably than Dog B, even if Dog A learns quicker. German shepherds learn really quickly but they tend to be intense and "driven" which can mean more work to make them reliable.
Lastly, you want to be very careful where you get you dog from. As previously mentioned, make sure the parents and grandparents have good hip ratings. Ask the breeder for proof. Also, make sure the breeder guarantees their puppies' hips. If they believe they're giving you a good dog, why wouldn't they?
The breeder should also have something to prove the parents have at least stable temperaments (not shy, safe to be around). In my opinion and I think the opinion of most breed-enthusiasts, they should have not just stable temperaments, but GERMAN SHEPHERD temperaments. By this I mean, good nerves/very confident/courage under threat, aggressive when called upon/protective, in addition to being stable. I mean what good is having a German shepherd if he hides under the table when someone breaks in?
GSD's are really popular and there are a lot of bad breeders out there, so you have to be careful. If you like, when you start looking at breeders you can post their website here (if they have one) or tell us about them and we'll give our opinions.