I have tested Nioxin System 4 for three weeks and am positively surprised by the results already. My hair feels fuller and healthier, and I experience less hair loss. The scent is a big plus – fresh and minty! The shampoo is concentrated and lasts a long time, which makes it affordable. But the biggest boost is the leave-in mousse – I thought it would make my hair greasy, but on the contrary, it stays fresh all day, despite daily use. A new favorite in my hair care routine!