I am currently using this shampoo. I have coloured hair that I dye myself and I do find this works OK on it. The colour does not strip and stays bright, however I do find it a little heavy on my already thick hair. Price is not cheap but does go on sale and thats what is expected from a good quality shampoo.

It's a nice product. Not sure about the colour preservance, as I didn't really see difference. Prefer a purple shampoo for my blonde. But it left my hair feeling soft.