I did mine at Walmart and had no problems. Mine had all the immigration requirements in a folder for different countries and the specifics were correct. They also had a guarantee to redo them for free if they were refused. I think it depends on what country you are from and how well the person taking them is trained.
And most small independent photos stores do them too, just take the spec sheet with you just incase. There is a privately run photo shop in the town I live and they do them, I called last week to check.