Airplay is good if you want to stream a limited, short piece of media. What most people do is hours of background music, and for this use case it's a bad solution:
- having your iPod/iPhone constantly stream will kill your battery life
- the iPod/iPhone hasn't limited storage
A much better solution would be to have a server streaming to your Beosound8, controlled by a remote app on your iPod/iPhone. So your pocket device is using battery when you change tracks or volume and sleeping at all other times, so you still have battery when you're outside and it counts. Plus you get as many track as you can put on your server hard drive.
Here's a my suggested setup: mac server in a cupboard, ipod itunes remote app, apple tv and your choice of b&o speakers.