First of all, if you're hesitating between this and number 323, Extra-Light Platinum, know that this is more forgiving. If your hair isn't quite pale enough--and it needs to be almost white before getting 323 anywhere near your head--then opt for Platinum Beige. My hair has really been through the wringer lately, sort of like the hair version of Texas Chainsaw Massacre, and this finally got all of the yellow out without making it strangely blue (White Beige) or doing nothing (Extra-Light Platinum). I'm sure 323 is brilliant if you are able to get your hair that light without it falling out, but if not go for Platinum Beige. It's a really nice, almost-natural white, like the color children have. Even better, it doesn't make hair fried, yet lasts much longer and is much more effective than the semi-perm toners. If you're going platinum, I highly recommend this.
EDIT: This is now discontinued, which is awful as it was such a great toner...sigh...the Clairol website has listed some equivilents among their other products, although I haven't tried them yet.
It worked fairly well after bleaching the crap out of my hair. I used 20 vol. clear developer. I would not recommend using this unless your hair has been bleached to the color of the inside of a banana. It completely took out the brassiness, leaving platinum blonde hotness, and I will definitely be purchasing again.
Yay, I finally found something to tone bleached hair with properly. I used platinum beige because I wanted something that wasn't too cool or warm in the blonde shades, and this came out perfectly! This was very gentle and killed all the yellow and brass I had in my hair. It is for VERY light hair so it won't work on non bleached hair. This came out a really light ash blonde, so it looks awesome. I am going to keep using this dye after my bleaching from now on. I will buy this again!