Hi Aussie, I store my QB carbon in my car on a regular basis and so far have had no issues.
I have put a strap on the handles above the front and back doors going across the car. I store my paddle in a bag and hang it on the straps.
It is great for cartage because you don't have it taking up space in the body of the car and it is out of the way.
This works for me.
ET.