This is the fan I referred to. The roof vent Fantastic fans change the air in the rig. As far as personal air movement goes, comparing the air movement between the two is like comparing performance between a Ferrari and Ford Escort.
The ENDLESS BREEZE
BY FAR
Is the most economical fan I have ever used. Even when I connect it to a AC/DC converter, the AC wattage is incredibly low actually insultingly so as compared to an outright AC fan. How much air does this mean? It means set on "1" the lowest one ampere setting I could not ignite a BIC lighter at a distance of six feet. At ten feet, set on "3" high, at ten feet distance it makes my eyes tear up. At TWENTY FEET DISTANCE, set at the doorway of my umbilical connected building the breeze is appreciable. And it is blowing out the entire room through the far open window.
These things use a Japanese SAMSUNG permanent magnet motor. Not just any permanent magnet. The pull is so strong I suspect the magnets are made of N52 Neodymium. To me this means "Economy of Energy". My original Endless Breeze (I have 3) is still working good. It has many thousands of hours of # 3 operation on it.
But it cannot be compared to a roof vent Fantastic. Two fans for different purposes.