No shooting please.
Remember the pen is mightier than the sword.

If it was a mechanic with knowledge of your vehicle I would listen and make an informed decision based on the information I collected. If it was an afficianado of the type of car I drove I would do the same. If it was some one I had no idea of I would still listen and then maybe do a little digging to see if what they said could be true and then make an informed decision. I think I would be a little reckless if I did not check the facts before allowing a loved one to ride in the vehicle.
Don't push it over the side you can fix almost anything.