diy notebook cooler power questions
 

So I just bought a Asus G71GX laptop and I was looking into buying a cooler. I've found a few very popular ones:

Cooler Master Infinite
Newegg.com - COOLER MASTER NotePal Infinite Notebook Cooler Model R9-NBC-BWCB-GP

Zalman Notebook Cooler
Newegg.com - ZALMAN Notebook Cooler Model ZM-NC2000 Black

I've heard mixed answers about which is better, so I'm guessing they are similar in performance.

MY QUESTIONS:
The cooler master runs on a 90mm fan. Is there something else that makes it so good? If I'm correct, it runs off 1 5v USB slot for power, so basically a slower 90mm case fan. Is there something else that makes these coolers as good as they are? The zalman looks like the metal might work as a "heatsink" since they advertise how its high quality and treated and stuff.

Also, could running a 12v fan at 5v do any damage to the usb port or the mobo? I'm assuming not but I just want to check.

thaanks guys!