I don't use the express with my 990, it's in the bedroom connected to my Onkyo. The AE is very easy to configure. It can be used as a wireless router and/or as an itunes device. iTunes transmits to the AE using Apple's lossless codec, so there should be no degradation in sound quality. You can either use either a mini-toslink connector (digital) or a mini to rca (analog) converter. The new version of iTunes will broadcast to multiple AE's, so you could theoretically use them for whole house audio. The AE also has a usb port so you can relocate your printer or add a network printer. It's a very nifty device.