The card with the fan in the center would stay cooler and probably OC a little better. However, it blows the head around inside your case and you should make sure you have enough case airflow. The cooler with the blower design would exhaust the heat out the back much better. While it doesn't keep the card as cool, it does get rid of the hot air and helps keep it from circulating around your case.
Normally the cooler with the center fan is prefered. But, I tend to like it to exhaust.