It works for ME. I'm one of those people who is sensitive to certain noises, like styrofoam rubbing, or high-pitched drilling. Squeaky brakes are one of those noises that make both my eyes go into the same socket and give me goose pimples.

I will yell loudly WATCH IT! at kids- not because I hate them but I often see kids running right out into the street without looking, or rollerblading or scootering right out into the street without even LOOKING to see if anyone is coming. I can tell it startles them but it's a lot better than if I had to swerve or screeeeeecch to a halt and do the Flying Nun over the handelbars. Sorry if it bothers you kid, but I'm not breaking a collarbone for you.