It depends on the vets at Banfield. I use the Banfield on Aurora here in Seattle and have nothing but praise for it. I have never had to wait for an appointment. The preventative care plan allowed for a very early detection of a previous dog's lymphoma which allowed for a treatment options and a very good 16 months after initial diagnosis of an aggressive cancer. The prices are very reasonable for Seattle and there are substantial discounts. I have not encountered any prejudice against GSD's or pitties. An added bonus is that none of my dogs fear going to the vet due to the location in PetSmart so it's not always a negative experience.
Here in Seattle we have a branch of PIMA which has an excellent Vet Tech program. Our Banfield has a lot of students and recent grads working there so they are really up to date on treatments and techniques. I would check the reviews on your local Banfield and try to meet the vets.
Some posters don't like the vaccination protocol. That is something to consider.