I agree this function is totally crap IMO..previously I had an Audi A6 with the same feature...however it actually worked as it should.
I took this to the dealer for the over sensitivity issue and not switching off. However they wanted the car for 2 days! I dont think they are faulty, they are just crap tbh.
Also agree with RR, they can give wrong signals to other drivers, I have had a couple of instances where people think they are being flashed....as a signal or IN ANGER....beware of their use.