Honestly, I bought some stronger "quiet" fans, and they were anything but. Again, I concede that you can find fairly quiet fans that perform well. But I was looking for a nearly literally silent fan that didn't need a high CFM. I don't think any of the higher performing fans, even when they market themselves as silent, were really silent. I've seen a lot of companies play with their dB numbers and call something silent when it isn't. In the case of the Cooler Master, the CFM is so low that physically speaking, it can't be anything more than silent. So my stance is that fans that rate themselves as 20dB really isn't. I've tried a Hiper fan rated at that speed, and it was much louder when I actually tested it.
Now, if there really are fans that have the same noise level and performed better at a decent price, of course, I'd want that more. I was just pointing out a no-brainer for those who want true silence with no regard to CFM.
Your point is well taken, and I think we can agree to disagree since I don't have much more to say on that matter, and I'm happy with my current home set up with the Cooler Master fan.