Do you think all salt mixes are created equally? Well, we all know that they aren’t, but does it really matter? If you perform regular water changes with any salt mix that carries even a halfway decent reputation, then you’ll likely not run into issues with coral growth or algae, or any of the other aspects that allow certain salt mixes to amass cult-like followings. Additionally, if you dose anything to the aquarium or run calcium reactors, the importance of the salt mix diminishes as you can replace specific substances on demand instead of during bi-weekly water changes.
So, long story short, it doesn’t matter too much which salt mix you use. That doesn’t mean you can’t develop a loyalty to a brand, but any statements about your tank looking better with salt mix A versus salt mix B aren’t based on anything other than a subjective experience that may not even be tied to the salt mix at all. Now, if you do rigorous testing and correlational studies of your aquarium, then perhaps you could make some sort of educated decision about which salt mix is best.