I buy most of my fish from petsmart. I have had more luck with them then anywhere else.
All of my tetras came from there (going on a year old, at least in my tank)
my roselines came from there and even my current pair of rams came from there and I haven't been able to keep a pair of rams alive from anywhere else I go. All my local LFS fish die within 2-3 days. Petsmart gets my business especially when they have their sales.