I had a problem with automation rules being not applied and it happened to be due to the fact that certain products had a default shipping service assigned.
When I wanted to see which products had a value assigned in the product list I realized that there was not such field/column to add to the view and hence I had to check product by product. I am not sure that even exporting all products I could detect those with a default service already mapped.
So this would be the spec:
As a ShipStation user I want to be able to see which products have a default shipping service assigned so that I can do changes or verify correct mapping.