I say, go Antec, OCZ, Thermaltake (iffy), CoolerMaster, Rosewill, or Fortron. Rosewill is relatively new to me, but they seem to be pumping out high quality pieces.
Go with anything above 500 watts, its much safer that way, because if a powersupply says its rated for 520 watts, thats a peak wattage, it might not be constant there. Antec is a good company, their wattage ratings are constant at what they are rated, mostly.
In the end I say go with Antec, OCZ, CoolerMaster or Fortron.
Maybe go with the OCZ Modstream 520watts. Thats what Im waiting for still, newegg messed up my order.