Is Purina good or bad?

Purina and Pedigree get bad names from a lot of people. I happen to know many people who have had a lot of success with it. My neighbors dog could not tolerate any dog food except Purina ONE, White works well. I have used Purina and Pedigree in the past myself and had good luck with it, and only switched because I have 3 dogs , all different ages, so I switched to something I could feed them all.