Please note, those of you who are purchasing this to add an additional fan to the 500DX case, it is not the same as the ones provided in the box. The ones included in the case have:
Fan speed (rpm) 900
Noise level (dB) 17.1 (even here we are not completely silent)
Airflow CFM 55.8
while this one has:
Fan speed (rpm) 1000
Noise level (dB) 18.8
Airflow CFM 61.2

So, you gain in airflow but the noise increases noticeably in practice. To be considered silent, it should be (subjectively) below 16db. Therefore, you will need to adjust the motherboard (dc control from UEFI/BIOS) to reduce the speed to 800 rpm, which gives less than 16db.

If you are not interested in adjustments or have an older motherboard and want to directly connect a fan to 4pin/molex and have it run at low speed, it is better to go for something like the Scythe KazeFlex 120 (800rpm) to keep your ears quiet.

It is completely (at low speeds) to almost (at full speed) silent! Often, you have to look at it to see if it's working!

The fan came with the case I bought, so I can't tell you about the packaging. It is quiet up to 800rpm and even at full rpm, the sound is not annoying at all, you only hear the airflow and nothing from the motor. I gave it 4 stars because it doesn't have a sleeved cable, but it is completely black and doesn't have rubber coating for perimeter vibrations. As a value for money, it will definitely be one of the top choices, in terms of performance the SW3 fans are slightly better with fewer db but more expensive.