This is possibly because Corsair already for little money to RAM with "heat pipes", the plugged aluminum panels equips. The ensure that the heat evolved evenly distributed and can escape more easily. Heat can greatly reduce the life of electronic components.
Speed-wise, the RAM is felt also very good, and I have since made no accurate tests. For normal use the standard RAM modules are anyway quite the same pace as it is primarily important that you have enough RAM.
This time, too, I again get exactly what I ordered and priced for the quality of RAM is also favorable.
I would Corsair XMS RAM at any time buy back as long as the price does not go up much.