I've always used Redken Blonde Idol shampoo for platinum highlighted hair but unfortunately they've stopped making it and I've finally used the dregs of what I had left. It took away the brassy/yellow tones without having to resort to 'purple' shampoo as this always sends my hair very dull with a lilac tinge, even if washed straight off and having tried several brands. Does anyone have any recommendations please? Pureologys Perfect 4 Platinum was a close second but that's been discontinued as well 