So far: Mangrove PuraPhos, BRS high capacity, Warner Marine phosar HC (same as BRS high capacity), Kent PowerPhos, TB aquatics smart reef (same as BRS regular granulated)....
Some wet, some dry, some dusty, some not so dusty, some with fine granules, some with large granules, some with small and large granules, some expensive, some cheap. all work fine and even the dustiest rinse fine if you have a reactor and run a gallon or so thru it into a bucket during water changes. The high capacity GFO is by far the least dustiest (which really matters not unless you cant rinse as described above).