Not even a hint of blue-ish shade on my grey hair after holding not 10-15 min, per directions on the bottle, but 20. It does work well as a shampoo, it just doesnt make sense to pay that much for such a small size shampoo bottle.
In my case it didnt work on naturally grey hair.
May be for someone else it will.
I requested a refund and was pleased with quick reaction and positive response of iHerb Customer Care. That alone allowed me to give 2 not 1 stars.
Doesn't dry out hair at all. The product foams moderately, has a light pleasant aroma. I don’t have the opportunity to keep it on my head even for 5 minutes, so I can’t say that it somehow drastically affects the color, except that it slightly neutralizes the yellow. I also bought a pair of shampoo conditioner. The couple looks after their hair perfectly! Hair after washing is soft and manageable.