If you want good fans, get a Delta Tri-Blade or the Panasonic Panaflos. They own all, hands down.
I prefer the Delta 120mmx38mm Tri-Blade High Speed SHE Fan. It pushes out 141.96 CFM at a relatively low 52.5 dBA.
Or if you're hardcore enough you can even get the Delta 120mmx38mm Extreme High Speed.
220 CFM at a good 65 dBA. The ownage.
Delta and Panaflo fans are expensive for fans, but you get what you pay for.