In-line Fans!!!

Hello to all RIU viewers,

I was wondering if anybody can help me choose a quiet,reliable in-line fan? Was looking at a few but can't decide! Here is what i was looking at and maybe someone can lead me in the right direction.

Soler&Palau,Active Air,Can Fan and Vortex...Looking for honest opinions!

I have a 6" active air 400 cfm, and I am happy with how quiete it is. It runs 24 hours per day, and so far so good. I also am running an inline regulator for the power because as of now i am only using about 1/3 of the power. It also helps to keep it quiete. I think you can get those regulators (they are called speed controllers) from Harbor freight Tools for about $10. Mine was $30 for the same one.