Which hairloss shampoo? Nexxus products or Nioxin?

I have been using Nioxin shampoos for almost 2 years now. I started with system 1 but have since moved to system 2 with no stop in hair loss. As I am only 21 years old I want to at least slow it down as I know there really isn't anything that can completely stop it nor help grow hair back. Has anyone used both Nioxin and Nexxus VitaTress Biotin Shampoo? Which worked better? I know they have similar ingredients so if one doesn't work does that mean the other one likely wont? Any suggestions will help. My frontal receding hair line is hereditary and I believe is worsened by stress as I am currently deployed to Iraq and in the Army. Thank you, suggestions are appreciated...