Does anyone know why the PC Power & Cooling Silencer 610 and 750 watt (I didn't look at any of the others, it may be the case with them, too) are so hard to find? Newegg, Amazon, and Tigerdirect, all which I usually shop at, don't carry them or are out of stock. Are they becoming less popular, or are they so good that everyone is buying them? I was able to find them eventually from a little looking around, but I just wondered...