I use reef crystals in my reef tanks and am pleased with it. I use the regular I/O for my fish only tanks as well. I think it mixes well enough, has the essential elements you need and it's one of the cheaper salts out there.
everyone will have their favorite and like said above none is really better than another. I;ve tried a few brands and have always come back to instant ocean.
180g Reef - 60g Rimless Reef -90G FOWLR- 125g Malawi Cichlids- 40b REEF- 34g Fresh Planted-working on- 20L FOWLR- working on
I have a mix of many different saltwater fish amongst my tanks, but I love my Tangs most of all.