PetsMart can have good vets, but becuase they are a franchise the vets hands are bound by the rules of petsmart clinic practices. This means to get to Point D you have to go through A, B, C first. No jumping, no leapas of logic, the vets MUST do things becuase they are the rules.
They must vaccinate on this schedule, they must vaccinate for these things, they must medicate in this way, etc etc etc.
You are better off IMO in a private practice where the vet can flex for your unique situation instead of it being a checkout line for vet care.