Corsair has better PSUs - tell us your full system so we can give you better advice, Mobo, cpu, gpu...
PC Specs will be:
CPU: Intel Core i5 3570k
Mobo: Asus P8Z77-V
Ram: Corsair Vengeance 4x2GB - 1600 Bus
HDD: WS 500GB (32 MB Cache)
GPU: HD4000 (I would Install AMD 77xx or 78xx Series GPU Later)
OD: ASUS DVDRW 24X Sata
CPU Cooler: CM V6GT or CM V8
Case: Cooler Master Storm Scout
PSU.. Still Thinking About it.
Anyways.. So the CM GX Series 750W or Corsair Enthusiast Series TX 750W or Corsair Gaming Series GS 700W would be Enough to Crossfire 2x AMD Radeon HD 7870 in Future or Is it Recommended & Better in Performance?