I also like instant ocean. Cheap, readily available and has everything a salt mix needs. lol
I use regular I/O for my fowlr
tanks and the reef I/O crystals for my coral tanks.
Salt mix is really in the eye of thebeholder, everyone has their preference but in the end they accomplish the same things.
I've tried other salt mixes and really couldn't see any difference so I am back to I/O.