I have 2 tanks and I used FloraMax in both tanks. No issues with clouding, no issues with PH swings. I did not rinse the substrate in either tank, straight into the tank and I used a large plate so as not to disturb the substrate while filling. I have not had any problems with soupy water when replanting or when vaccuming. Also bought at the local Petsmart. One tank was the Red, the other was the black.
I have Cories in both tanks, Pepperred in one, Juhli's in the other. They are as happy as can be, barbels are in great shape.