I am thinking about buying this kind of phones for the office, I have implemented a VoIP PBX, based on Asterisk working on a Debian server.

We use mainly Skype for our International calls, and Asterisk for the in-office calls, I know there are Skype Wifi phones also in the market, but I am faithful to my Linux PBX :), so I am thinking about trying the integration between Asterisk and Skype.

Linux is always there to help you keep your office costs low, it acts as a PC with no need to pay for licenses, also as server, and as you can see even as VoIP PBX/Gateway, which keep you international calls at low rates.