I was using one with henna (not coloring) and morrocan clay, but it's been discontinued boo !
I really liked it, you just have to slightly wet the shampoo bar and foam on your hair, lol it takes a few seconds so i agree even if you think you're just rubbng salt into your hair, do lather it up and you'll see the foam appear quickly. Make sure you don't leave it in the shower where it can get wet accidentally because then it will melt like a classic soap does.
One i want to try some day is i think trichomania (i don't know, french and english names change), anyway it's their best seller with coconut for dry hair.