Value for money leader is the 212+ at $30. It performs very well and is actually not to loud unless you are heavily overclocking the CPU and need dual fans at max RPM to keep it cool. A single fan on auto would be quite quiet.
The N520 is not a high performance cooler, but it is quieter. If you are running stock cpu speeds, the n520 will do a good, quiet job. If you plan to overclock, the 212+ will do a far better job.
The 212+ and the N520 is priced in Belgium. I just want the most quiet one that does the cooling.
I want to put this in my pc:
Asus AM3 M4A89GTD PRO USB3 HDMI DVI VGA DDR3
AMD AM3 Phenom II X6 1055T 2.8GHz BOX
ASUS ATI 5850 Direct CU 1GB DDR5 voltage tweak ed.
Kingston DDR3 4GB 1333MHz (2x2GB) CL9
Antec true power 550W
coolermaster 690 case