I bought and used both. I used RR longer than CK. But I am anti layering lately. Both are good products, but not good enough for me to go back to. My hair is so thick that I went through a bottle of RR every 3-4 weeks. Ck lasted longer but I could not stand the smell ( I have a Bionic Nose). Ck also made my hair feel weird, kind of plasticy. RR always felt fine. Again, its my whole aversion to layering philosophy lately. Check back in a few months
2C/3A auburn hair.
between shoulders and BSL