A few years back, 2000 I believe, omna changed formula's to be just like sust. They both contain 30mg test prop, 60mg phenyl-prop, 60mg isocaproate, and 100mg decanoate. Exact same amounts of the exact same esters. Omna used to contain hexanoate in place of the decanoate I believe, which is a shorter ester. So omna built up quicker and gave more mass and bloat than sust. As of 2000 though, they are the exact same.