FedEx International Shipping Declared/Insured Value

Hello, we use Fedex for most of our international packages.
We generate our own commercial invoices to ship with International packages. We are thinking to purchase the FedEx insurance at a lower value (so the declared value/Commodity price in ShipRush would be lower than on the separate commercial invoice). I'd like to confirm with you guys whether this is OK or there might be potential problems?

Thanks