The Corsair HX1500i wins in 4 out of 9 comparable specs, with 3 ties. Its biggest advantage is PCIe Connectors (40% better).
Toughpower GF3 1200W wins in 2 specs (SATA Connectors: 50% better).
Recommendation
Choose HX1500i if you want the best overall performance — especially pcie connectors.
Choose Toughpower GF3 1200W if sata connectors matters more to you.