i switch up brands, it just has to be sulfate free because I have keratin in my hair. all of the sulfate free ones I tried seemed fine, tried a few diff brands, no preference, I just have to switch every few months between brands because I have oily hair and I notice if I use the same one for too many months in a row my hair gets oilier.
I use shampoos that are organic, and usually only a couple of bucks. I'm vegan, so the main thing I look for is that they don't test on animals. I don't really care what it does for my hair since I never notice the difference anyway ha.