Or is it all a big con like skin care?
My hairdresser was appalled that I use some high street shampoo & conditioner on my hair (elvive I think) but in the next breathe tried to sell me her own super delux stuff, so I naturally assumed it was bollox. My hair has been much more silky though and I didn't need to wash my hair until today (so 4 days instead of the usual 2)
Are the expensive ones really that much different?