For amateurs, the blue LED on the white body of the key is the most beautiful effect and allows you to instantly know if your connection works.
At the same location a Netgear WG311 PCI card, reception from my Freebox WN111 v2 and this key is much better. Certe price doubled, but you must know what you want :)
(Driver used: WN111v2_SW2.1)
Update December 2012:
The beautiful blue LED was finally extinguished a few days after the end of the 2-year warranty.
The positive side is that the key still works after more than 3.5 years of service.