I have a Dynavin N6 in my 2000 540i Touring which has nearly the same DSP sound system. It's excellent if you want a fuss-free head unit. Bluetooth and iPhone connection work seamlessly, it plays CDs/DVDs, has a pretty decent nav setup, it works with the steering wheel controls, and it has the ability to use a rearview camera. It's completely plug and play in terms of wiring— no cutting and splicing required. And it works with DSP properly, whereas a lot of eBay head units don't. That made it the clear choice for me.

__________________
2003 X5 4.6 | 2000 540i Touring

Formerly owned:
2004 Range Rover | 2000 M5 | 2000 540i/6
1995 750il | 2003 Mercedes S500 | 2003 540i/6