Congratulations on being so serious about socializing--it is really important and will pay off big time in the way your dog deals with his world.
I've never used any of those carriers. Can't comment on that--except to say it's going to get heavy with a GSD puppy.
I think you have to weigh the risk-vs-reward of socializing at a young age. IMO, socializing is too important to leave a puppy at home until they've finished all their shots. I took all three of mine everywhere with me that I could from the day they came home.
Clearly, don't take the puppy to places where other unknown dogs have been--dog parks, the patch of grass outside petsmart, etc. But there should be no problem taking the puppy with you to many places where they can meet people, see and hear new things. Most parks, playgrounds, stores, sidewalks, homes, vet's office--all these places should be fine.
Just riding in your car to different places is good socializing, even if the pup never gets out of the car. Go through the car wash. Park at WalMart and watch all the people. And don't overlook all the "socializing" that you can do in your own home---to different noises, grooming routines, stairs, floor surfaces, etc.
Just use common sense. But I don't think you need to be overly germ-phobic with puppies.
I've never used any of those carriers. Can't comment on that--except to say it's going to get heavy with a GSD puppy.

I think you have to weigh the risk-vs-reward of socializing at a young age. IMO, socializing is too important to leave a puppy at home until they've finished all their shots. I took all three of mine everywhere with me that I could from the day they came home.
Clearly, don't take the puppy to places where other unknown dogs have been--dog parks, the patch of grass outside petsmart, etc. But there should be no problem taking the puppy with you to many places where they can meet people, see and hear new things. Most parks, playgrounds, stores, sidewalks, homes, vet's office--all these places should be fine.
Just riding in your car to different places is good socializing, even if the pup never gets out of the car. Go through the car wash. Park at WalMart and watch all the people. And don't overlook all the "socializing" that you can do in your own home---to different noises, grooming routines, stairs, floor surfaces, etc.
Just use common sense. But I don't think you need to be overly germ-phobic with puppies.