I'm a fan of taking my prop's off when I finish flying - and I store my Mavic Pro Platinum without anything on the motor hubs. I figure that this provides the following:
1) The compression springs that you push the prop's against are allowed to relax and keep their original shape/length since they are not continuously under compression.
2) My prop-blades are stored in a fabric bag, and lay in a slot in the case I carry the MPP around in. That way, they are under no stress or odd pressures that would put a bend in the blades or de-form them in any way.
3) The last point is that as they are put on and taken off before & after a flight, I get the opportunity to check all the prop's (hinge flex / physical damage), to make sure that they are OK, and if not, I know to place an order for a new set as soon as I get home.