everyone is going to have an opinion on which salt is better. depends on what you keep and what else you add or take away. I prefer scripps because it is easy and I just add a little two part to it and don't worry about it. what you don't want in salt mixes- phosphates... what you do want , ca, alk, mag. I don't worry about anything else because I have seen too many successful tanks without any other things added.

This is a 1200 reply discussion on salt mixes if you want to read
http://reefcentral.com/forums/showthread.php?t=1287118