When I'm at home at night, which is usually the case, the Focus sits in my front driveway, right by the house. If anyone walks within 20' of the car, the house motion detector turns on a bunch of lights and the whole car is lit up. And it's then bright enough to see everything with the security camera, which is pointed at the car.
The little blinking light just adds to the system.....and gives more security when I'm parked away from home. This little mod is cheap enough and fairly easy to install.....only two wires. Worth the trouble for me. Since I've been installing this blinking light mod (ten years at least), none of my cars have been touched, not at home or elsewhere. (fingers crossed)