I bought three of these little devices and installed them in my house the other day. An old laptop is the music server on which I keep about 4,000 songs, and from it I can send the music wirelessly to stereos in the kitchen, the living room, and upstairs. The kitchen stereo is a cheap Price Club item that cost me under a hundred bucks, to make sure that my mixes work on in-expensive stereos as well. A great mix is a good average that works on as many different sound systems as possible. I do not believe in mixing for a small Hi-Fi elite. In my living room I have the Gallo Reference Speakers and upstairs I listen to the cute red Blueroom speakers, named Red Buddha speakers by a friend. They used to be made by B&W, but now the technology has been licensed by a Danish company who is developing new speakers as well.
The little Airport Express can deliver audio to a stereo system in analog form via 2 RCA plugs, or in digital form, via a Toslink (aka lightpipe) cable. I am quite happy with the sound.
And, of course, when we tour, I can bring one of these along to hook up to a hotel’s ethernet connection in order to work wirelessly within a hotel room.
The Airport Express works with Windows and Macintosh computers.