I have been using Apple’s Airport Express for a few weeks now and am very happy with it. I use three of them at home to connect to different stereos in the house and I take it with me to create a wireless room-network in hotels that offer hi-speed internet via ethernet.
I discovered that the transmission of music to the AX does not work reliably with the older 802.11b standard. I noticed a lot of drop outs, which drove me crazy. I re-configured my network many times before figuring out that my music server, an old 400Mhz Pismo G3 Laptop, uses the old airport card which runs the 802.11b standard. I found a solution at OWC: the Aria Extreme PCMCIA card that delivers 802.11g speed for Apple and Windows laptops, provided they have a PCMCIA slot. Installation on my PowerBook was extremely simple. Turn computer off, insert Aria card, turn computer back on – Bingo!
At the Apple store in Santa Monica I bought an unusual cable that allows the AX to transmit Digital sound to an external D/A converter via a lightpipe. Now it sounds glorious as the AX is connected to an old Parasound D/A converter that sounds lovely. Unfortunately Parasound no longer makes CD players and D/A converters.