All that hobby stuff is low temp thermoset plastic, ideal for making molds for casting but the parts it creates are somewhat brittle and can cleave at any point on the x/y axis that the material is laid down on. In that example, it will probably work fine, but the wear items will most likely be cast from 3d molds. I asked once how much a mold for 64/65 taillights would cost and got the same 10-15k price range. Nice thing about that is you are handed a 'shoe' that can be given to any injection mold house and can be used to spit out perfect lenses in under 5 seconds a pair at about .18 a pop (in runs of 1000) . 3D has its place, but its still in its infancy, great for emblems if you could electropkate them.