flybull - Welcome to PPrune.
A380-800 driver. The A380F may never be built. After all the cancellations there are no orders for the model and Airbus has ceased development work.
(As you may be aware one airline is expected to cancel an order for the passenger version before the end of the year)
The A380F is 81 tonnes heavier than the B748-8F but is only expected to carry 10 tonnes more payload. The A380F was designed for 7.9 lbs/cu.ft cargo. The B747-8F is designed for 9.9 lbs/cu.ft cargo.