I was rear-ended in a chain reaction crash. There were 3 State Troopers by the side of the road who had just finished clearing an earlier incident and who observed me getting hit. Damage to the e-tron was limited to the rear bumper and the tailgate foot swipe sensor. Total cost $1,750.
For those who might be curious as to how solid the factory hitch is, here is a photo of it without the bumper cover.