We will be traveling to Germany and France in May. We will get the extra car insurance but there is a category of insurance called "Super Insurance" (which can only be purchased in Europe when the car is assigned) over and above extra insurance. It essentially doubles the already high cost of the overall car rental. Does anybody have experience, both good and bad, in this matter? Thanks.
See: https://www.ricksteves.com/travel-tips/transportation/car-rental-cdw
The "super insurance" is same as "super cdw".
Many people will advise you to buy it. Many, like me, just rely on the credit card protection.
Up to you what makes you feel comfortable.