Best protein treatments for color treated

I haven't really found anything that I'd call the "best" but I have Kerastase and Joico Kpac and I like both of those a lot. A warning though: I had just read that using a protein treatment on color treated hair could cause the color to washout/fade. I just confirmed this with my hairdresser. Has something to do with the size of the molecules of color versus the conditioner -- I think the conditioner crowds out the color molecule -- not sure if I have that exactly right. I think she said to wait at least a couple of weeks and that you shouldn't use it more than once a week. However, if I were you I'd check with your colorist or just check with someone at a salon if you do your hair yourself. I don't know if you should avoid protein altogether or not. My hair is bleached and I have a toner on it so maybe my instructions would be different from an all-over color. 

Thanks!!