What is the best kind of aquarium salt to get for a reef tank?

I see instant ocean is by far one of the most popular, however Someone told me at a lfs that the best was Seachems, because they go the extra mile to put more reserch into all of their products...I personaly prefer the seachem line of chemicles more than API, but API in my opinion is the step down from seachem. anyways, what kind of salt do the rest of the people on here use?