I grew up with Labs and just got my first GSD.
Labs are much easier dogs to own, I have to say. Much more mellow, active, but don't need copious amounts of mental and physical stimulation. Some people think they are stubborn, but I've never found that to be the case, especially since they have SUCH a strong food drive, they will learn to stand on their heads for a cookie.
My GSD pup is a harder type, and she's really been a handful. She's great, but definitely been a learning experience. My biggest challenge is her dog-reactivity. It's really been a lot of work, and I'm not sure if she'll ever be 100%, but we continue to work on it. Still, she surprises me every day with how quickly she figures things out, she loves to work, is really enthusiastic and is growing more confident and independent, which has been great to see.
I think I'd also recommend waiting until you're done school, and settled. What will you do with the dog when you're at work or school? Especially while it's a pup, they need to go outside many times during the day. Doggy daycare and pet walkers are about $15-30 a day.
Both breeds are intelligent and loyal. Are you going to do puppy and obedience classes? They aren't cheap, but are well worth the cost.
I find Labs are happy go lucky. GSD's are amazing, intelligent protective and independent thinkers, but tend not to be overly social with strangers, whereas Labs will pretty much welcome anyone into the house.
But all those things come at a cost too, you really need to work hard with them, because those qualities can work for you, but can also work against you.
Also, think about what lines you're going with. GSD's themselves are broken into several 'types' working, American Showline, WGWL etc. All have different characteristics.
Von Öhmke - German Shepherd Dogs
Labs are Show lines, smaller in stature, but bigger boned/boxy in appearance, and I find are more mellow. This is the Lab I grew up with.
The Field lines of Labs tend to be bigger, personally I don't like their heads. I find they are more hyper, and the only dog aggressive Labs I've ever met have been the field lines, but maybe it's a bad coincidence.
Whatever you pick, make sure you go with a reputable breeder. They do all the appropriate health checks and will be there to support you throughout the life of your dog. Their kennels will be clean, they can answer your questions and you should be able to meet their dogs (they may not own the sire).The dogs will be expensive. Plan on spending $1000-$1500. If a breeder is selling for less, I'd be suspicious. Not that more $$$ means a better dog, but less $$$ often means a lesser quality dog.