Meg..Lets say we put 20 tonnes in an A400M and 40 tonnes in a C-17. As the C-17 has longer legs it can carry its 40 tonnes further. At some stage the A400M will have to swap load for fuel to keep up. I would imagine that at a certain range the C-17 still carries 40 tonnes while the Super Albert can only cope with 10. Remember, the A400Ms range figures are only good if it can climb to its optimum altitude. Unfortunately it will be too slow and restricted, like the J, to a lower less efficiant level.
Just my guess, but we all know that stated max loads are only good for limited range. We are clearly not getting a strategic airlifter on par with the C-17, however, I don't think (even if/when it flies) that the A400M represents a value for money airlift solution for our deployed forces.
I do hope that I will be proved wrong, cos there's no going back and I suspect there's no money left for plan B!