Good solution but a person set on getting in only has to unto the Tenax fastener behind the door and put their arm into the car from behind the window, it is easy to reach the door lock and open the door.
you could put a Rotwieler inside the car to bite their hand off.
Serious though, on my car the door cannot be opened if it is locked with the key, and the Tenax fastener is most covered by the side screen.
