I've been reading the forums on this site for lingo, tips and information since I bought my 99' e38 740iLw/edc in Jan 08'. Lately I've been trying to gather all the info I can on audio upgrading to a good DVD-Nav Head Unit (HU) that will look good and do all the modern stuff (BT, Ipod, iphone, DVD, CD in all formats etc,). I've already overhauled the entire system EXCEPT the original HU. 2-way MBQuartz (3-pr), 2 X JL12W3, 2 X JL500, Continuum amp and ARC EQ (perfectly fitting in the dash cup holder slot). I purposely removed the CD changer (I shouldn't of) and DSP system (glad I did). I do know this- if you change the speakers, amps or HU the DSP BMW amp WILL HAVE TO GO. It will not operately "properly" without connecting to the original HU via IBUS. I went 100% iPod, but somewhere during the upgrade, I've lost my AM reception and recently my cassette player jammed (I use it only 2% of the time). I never changed the BMW HU so the dash looks normal. The system is (I'd say) outstanding. Very balanced, accurate, whispers or screams, bass is super-sub-deep but not boomy (and not really heard outside the car). It's really good. Thanks Stereo Installation (Fremont CA). But with all the talk about the Dynavin 3 and 4, I wonder does it allow you to retain the informational functions like OBC, Aux temp, Speed monitor, distances, etc? Has anyone successfully upgraded their HU in an e38 and with what unit?