I like Cora's breakfast menu choices compared to more traditional diners. I don't think the quality of food is any worse than any of its competitors. Don't mistake poor service with poor quality food.
And honestly, breakfast sausages are not gourmet cuisine. Hardly an indication of the quality of a restaurant, let alone a diner chain.
The service is most certainly hit and miss. Sometimes it's acceptable, other times it's just slow. As an example, our empty coffee cups took way too long to be tended to. In a diner, there should be designated coffee server who is around almost too frequently.