Quite effect from the moment of installation. Since installing, there's not been one fouling by cats, so 100% successfull up to now. (about 5 weeks)

Cautious to find the fastest, biggest microSD for reasonable money, this Class 4 Kingston chip is brilliant value for money and works superbly in my HTC Desire. Adapter was sent for the larger format SD also which was a bonus. And still not seen anything for better value since!