EVGA 650W SuperNOVA NEX650G Gold or Corsair RM650 Gold

I'd stay away from the EVGA SuperNOVA NEX650G (120-PG-0650-GR). It's based on the FSP Aurum CM AU-650M and they both suffer from the same problems.

The +5V rail whose voltage sags below the ATX12V permissible level of 4.75 volts at high loads.

It has poor fan speed regulation (i.e. uses linear regulation instead of the preferred dual-zone regulation) which makes them too noisy.