Quote - you can't parent them to more then one object, and you cannot apply mat poses to them unless they are parented.

This is NOT true! But you have to set the right parameters in the mat pose file.

Quote -
the one thing that props have that Figures don't is ease of creation. for a prop its as simple as load in poser, save prop, done. Figures have to have at least a rudimentry skelital system, even if its just one bone, so it is going to be more work then creating a prop.

Props are easier to handle and smaller in size (important if you need an object several times in a scene). "Smaller in size" means memory consumption at first.

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