I just picked up a new Zephyr to replace a failing briefcase made by another company. I know the Zephyr is supposed to be a more "squared off" design (with the bellow style opening to the main compartment) compared to my old ID bag, but it seems a bit stiff all over. Will the bag give a bit after use, like my ID bag (or a pair of well worn jeans)? I have only filled the bag and tried it in the house because I may possibly trade it back for a new ID bag. also, is the new ID bag any stiffer than the previous model? Any feedback would be greatly appreciated.