I chose this one right here for my intake and exhaust fans: Enermax enlobal bearing
For me I prefered slightly less then optimal air flow with low noise, over optimal or excessive air flow and more noise.
It uses a "magnetic barometric" bearing which suspends the fan in a magnetic field so there really really quiet. They dont move alot of air but I find them adequate for me. My case supports 90mm fans also but they don't make these fans in 90mm, only 80 and 120.