For what it's worth I've noticed that an Eagle Creek 18" Packing Folder fits perfectly into the zippered "laptop compartment" in the rear of the MLC. (Personally I think it's way too big to be used as an actual laptop compartment unless you have a gigantic laptop.)
But sticking a packing folder in there works brilliantly. You can pack the main compartment with plenty of space to work with while the laptop compartment is empty, zip the main compartment shut, and then slide the packing folder in at the end.
Stick a few packing cubes in the main compartment and you have a nicely organized bag that is very easy to pack. (I like the Eagle Creek Specter Cubes and Folders because they are super lightweight.)