Pardon the ignorance, but I'm under the impression that if you get rear ended with your tow ball mounted and such you risk chassis frame damage, even at low low speed impacts ? Kind of makes sense since most of the impact is concentrated instead of distrusted more over the whole bumper. My girl friend and I were driving in her Tahoe, and she was rear ended with the tow ball on. We were thrown a good bit out of our seat, considering it was such a low speed impact (~5-10km/h). Lots of damage to the car that hit us, not a scratch on the hoe.