Does the ';John Freida sheer blonde'; shampoo and conditioner actually work? How long does it take?

It slows the loss of color, it won't take time.Does the ';John Freida sheer blonde'; shampoo and conditioner actually work? How long does it take?
I use the sheer blonde high lights shampoo for darker blonde hair. I'm pretty sure it ';brings out your highlights'; by cleaning your hair like other shampoos to get rid of dirt and grime. It is non color depositing, so it won't change your hair color, which most likely means it will not be a process that takes time.