Stock vs NV5 silencer...

Which is better? The stock aluminum heat sink or the NV 5 silencer? Has anyone here compared the temp difference?

I am considering three options,

A) keep the stock aluminum cooler
B) Upgrade to THIS
C) NV 5...

So what do yous think? will a coper sink be much better then a aluminum? I tried to find a review of the NV5 vs the stock but had no luck...

Edit: Also how would I use the NV 5? it only comes with this...

http://images10.newegg.com/productim...186-120-05.JPG

notice my backy is a double! :mad:

http://img.hexus.net/v2/graphics_car.../6800U/DVI.jpg

EDIT: Well I just found out that the stock cooler is better then the silencer! :eek: There goes that idea looks like I'll be buying this one instead....

http://www.evga.com/products/images/...F1-EV18-01.gif