Originally bought this from a local store. I didn't think it would work very well because all you do is dilute and spray on, no scrubbing or hard work. I only managed to do half the drive with the smaller one I bought, I didn't notice much difference to begin with but gradually the part of the drive I had done became cleaner and cleaner and I could really see a difference between the half that was done and the half that wasn't. By this time my local store had sold out, but luckily I found it on Amazon. This is great stuff and so easy to use. I highly recommend it.