There's what you get when you only look at output ratings and fan size.
You have to understand that you get what you pay for, and name brands like Antec, Corsair, XFX, OCZ, and Seasonic all make flat out better units. The components put into them are just better. Period.
When you buy a cheap PSU, it doesn't matter how big the fan is, they probably just put the cheapest parts onto the board that they could that, which will blow up in a year of light use, maybe sooner. If you want it to anihilate the rest of your setup, go ahead - build yourself a new PC every year because of a cheap PSU. If you were smart, though, you'd get a good, reliable unit that will probably end up lasting ten times longer than the rest of your setup with no problems at all.