Vet advised against Costco dog food

My vet advised against feeding my dogs Kirkland dog food at their checkup yesterday. She said that almost every dog at her clinic that had bladder stones, and some needing surgery, were being fed Kirkland.

Has anyone else heard this before? She recommends switching to Purina Pro Plan, but it is twice the price. I'm worried about the quality of this food now :(

Edit: Thank you for all your responses! I don't mean to worry anyone, or talk badly about this food. I have been feeding it to my two dogs for a year now with no issues. It is the salmon and sweet potato one. I will be doing some more research and comparing these two foods, but it really does help and I feel better to know that no one here really had many issues with Kirkland dog food. Thanks again!