Best Power supply is hard to quantify. How do you determine what makes a good power supply?
Here are some categories to consider:
Price: Is it worth it to spend $250.00 for a really good power supply?
Efficiency: How much power is consumed to make the power. Someone has to pay the electric Bill! Low Efficiency may also mean more heat.
Heat: A good power supply should not run too HOT! This is not good for your air conditioner.
Sillence: A good power supply should not sound like a lawn mower.
Stability: A good power supply should not kill half of your hardware when it blows up. It should run for years and years without giving up.
Weight: This may seem strange, but a heavier power supply may actually run better. This has to do with better components and cooling fins. Real light power supplies are sometimes just built with inferior components.
Might be that there are many good quiet running power supplies made. I have had really good luck with Antec power supplies. I never buy the True models, only the standard models. I dont see the point in buying a stupid blue light. That will not make a PC run better!