I'm using a keratin shampoo and I like it a lot. It makes my hair very soft, manageable and shiny. I have long, dry hair that gets tangled very easily. If my shampoo is not good, I can't even brush through my hair after washing. But I have never had this problem with organic keratin shampoo. My hair looks and feels very healthy.
I should probably mention however that my keratin shampoo has lots of other beneficial ingredients in it like coconut oil and aloe. So it might be wrong to say that the keratin is responsible for these results entirely. I'm sure that the other ingredients are helping as well.