Does anyone have any knowledge or experience with the A400M?

It appears to be a new model of aircraft. From what I've gathered, the Airbus A400M’s four turbines are rated at 11,000 ESHP each, powering eight bladed Scimitar props through a reduction gear box.

That’s a lot of power for a gear box to handle. I'm wondering how significant the effect of the drag increase from such a large windmilling prop might be on the aircraft's performance? That is, if one of the engine gearboxes were to malfunction, and/or if an auto-feather system were to malfunction, during an engine failure?

The A400M's props on each side are counter rotating; achieved through the engine gearbox mechanism. All four turbines are apparently symmetrically rotating, so I think that the non-standard gearbox arrangement would be fitted to the two engines on the left side.

NB. I'm in no way suggesting or speculating here about the actual cause