Petco is trusted by over one hundred thousand Amazon.com customers in the US.
They sell Dr. Elsey's, Seresto, Purina Fortiflora, PetSafe, Greenies and other brands products. They have few thousand products in stock fulfilled from their own warehouse.
They are a Top 100 Amazon.com seller, ranked 98th overall. However a month ago they were ranked 95th. Seller rank is based on the number of positive reviews received during the last 30 days.