If you want a fan that moves about the same air, then you can usually expect "about" the same amount of noise. There are some quieter than others though. If you don't need such a productive fan, you can get some that are pretty quiet.
I was thinking about the Scythe S-Flexes myself. Responding to the first comment, I require two 120mm chassis fans, one intake and one exhaust. My budget can be considered unlimited, since fans do not exceed 20 dollars.