I cant speak for the Artic cooler, but the Zalman is pretty good IMO. I have mine on a XFX 5870 running over volted to 2.12vish(if I remember correctly)at 1000mhz. It still keeps the card under 60c will playing BF3 for hours.
If you Buy the VF3000, I would highly recommend replacing the stock thermal tape on the ram sinks with some 3M thermal tape. It will keep as good or better conductivity, but you will never have to worry about the ram sinks falling off, if installed correctly.