Are L1A's really that quiet? I have a cheap generic fan:

But they are rated at 24 DB. The 120 mm L1A is rated at 30 DB. I want to make the carpc quieter because the fan is driving me nuts...the PC is no where near quiet. But I can't tell if it is the fan making all the noise or if it is the wind bouncing around in the case that is making all the noise. Would it be wise to pick up a panaflo? or stick with what I have?