I am looking for a light thermal protector for flat ironing my hair. I hair QP Mango Butter, but it is to heavy. I bought QP Silk, but I didn't like it much. My hair dosen't feel silky. I have relaxed fine hair that is just grazing my shoulders. I have heard good things about Biosilk silk therapy and NTM serum. Which one would give the best results for heat protection and flat ironing?