I have the VF700 AlCu installed on my 6600gt (AGP) and I am thouroughly impressed. I know that the card they tested it on was the 6800gt, but my experience with the 6600gt was gravy. Lowered load temps from 80-93C to 51C constant. And that was on the 5 volt quiet setting.
I used Arctic Silver 5 as well.
Just my experience.
Also: look at the PC they used for this review...how many of you have cases that don't have the waffle opening on the back of the case, on the very bottom? I know that the majority of cases I've ever seen have that opening, which would improve airflow around the cards.
Just a thought.