I like Petco because they have a good selection of quality merchandise for pets. They are very similar to Petsmart; however, I've found their prices to be a little higher. They also offer low-cost vaccination clinics and various other services. Petco also raises money for homeless pets and shows concern for animals in the community.
They sell pet supplies for almost any type of pet, and I've always found the staff to be helpful and friendly.
PROS: Quality merchandise, friendly staff, variety of services
CONS: A little more expensive than some other stores
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