Performance Issues with SalesForce?

We are seeing various users who are seeing drag on page load when viewing and refreshing cases in SalesForce. I have a case open with support to help look into this but I wanted to see if anyone else has any experience with ZIA configuration and SalesForce. There are not blocks or authentication issues. So I wanted to see if anyone has had to bypass Sandbox, or SSL Inspection for SalesForce to resolve issues.