Another salt thread, lol. Just what we need.
I do understand however, why this is an important and recurring topic, so I'm really not criticizing.
That said, over the years I've probably used salt mix mentioned along with a few nobody has mentioned. And whenever I've changed to a new mix, I've always used it exclusively for at least 8-9 months to really get a good feel for how well it works for my tanks. Hands down, the best salt I've ever used is ESV. But the cost was high, and when I was no longer able to get it in anything larger than 100g units, I switched to Fritz RPM. The Fritz is the second best mix I've used. It is extremely consistent from batch to batch, and always very close to the published parameters. It mixes clean with no sediment or residue. I'm very pleased with it since switching to it about 18 months ago.
IO and Reef Crystal are by far the worst I ever used. They are cheap (especially IO) for a reason. Never again for me.