I usually get a bucket or 200gal box of reef crystals when I'm down to 1 bag or half bucket but didn't when I bought the Sachem (that's all I had at the time). I also Usually have a 5 gallon bucket aerating for at least 24 hrs. I'm just a di-hard IO fan I guess. It was the first salt I used about 35 years ago, I think there was one other salt mix at the time and have had consistent results all these years, so I didn't have much choice at that time. Nobody really new much about the salt water fish let alone corals back then. If you had something hat lives for over 3 months you were doing good, sad but true. Even though I'm pretty well set on IO reef crystals I'll try others just because that's the nameof the game. It is cool, with all that has been learned about the keeping of saltwater creatures thru the years, to have fish, critters and corals not only live for many years but to thrive and reproduce. Just like salt this hobby has come a long way, Much of the "oldshool" ways were not wrong just not enough (some stuff was stupid looking back at it now). I have found that using the knowledge of what I have learned thru the years plus applying a good bit of the new technology has been my formula for successful saltwater habitats. This holds true for the advancement in the formulations of salts.
I'm sorry I ran off on a tangent, you are right by saying that aerating the salt mix does help to mix it quicker. All I guess I meant to say is that IO salt mixes /dissolves much quicker, for me than Seachem. They're both good salts and I'll say it again, I think whatever works for each individual hobbyist is the best salt for them.