Yes, use the original packing to protect it from further damage during shipping. Why wouldn't you? You will get back your original box and Styrofoam packing, unless they ship you a whole new craft, which they have been known to do. But if you don't send the RC, they will likely send back your original packing. If they send you a new craft they usually link it to your RC if you ship the RC too, but if you don't send the RC, and they send you a new craft, you'll need to link the new craft to your RC, which not a big deal, very easy to do. Usually they will tell you whether or not to ship the RC. Most of the time I haven't sent the RC with my returns.
I just sent the inner polystyrene wrapped in Black polythene back as I wanted to keep the outer cardboard mint for when I sell it on to fund the P5P.
They sent the inner polystyrene back in a perfectly sized cardboard box, which I used to send it back the second time.
