As we all know the PSU is one of the most important yet under-estimated components of the modern PC, it is pleasing to see that most of the nominal wattage is available for the 12V line as it should be with a modern PSU. The sharper amongst you may also have noted that the 150w from the 3.3V and 5V lines plus the 450w from the 12V lines doesn't add up to 550w so the ratings might be slightly on the conservative side which is no bad thing, I'm inclined to believe that the 12V lines have been slightly over-estimated in that both lines cannot produce 25A and still be only 450w. The only way to see how good it is is simply to test it now.