[citation][nom]A Bad Day[/nom]What's the difference between "High Pressure" and "High Airflow"?[/citation]
These thin fans have low air pressure. That's why its not even listed on some models and why I said; "meh" The thin frames do not allow for good air pressure, which would make them useless for pushing air through a thick heatsink or even an air filter. More static pressure means that the air can be pushed through a resistance better.
Airflow simply means the amount of air that the fan is capable of pushing at a certain rate of speed.
Think of this as a water hose, a thick water hose can move lots of water but would need a lot of pressure to produce a jet. When you put your thumb over the end of the hose, you create a blockage which increases the pressure without increasing the flow of water. Since you've restricted the flow with your thumb, the same amount of water is trying to squeeze through a much small opening which increases the pressure many times.
If you turn the hose on 1/4 of the way, your water flow may be 50 CFM, or cubic feet per minute. Turn the faucet halfway, and it may be 100CFM. Same with air flow, the CFM rating is how much air under ideal conditions a fan may be able to move in one minute.