$1800 is a tough sell.... but if the sound difference is significant to warrant the extra expense then I'll do it..

I think I'm going back to the dealer with my iPod to test out the standard system.

never tried it so I might as well know for sure...

One of things that I want to test, when I get my X5, is whether the DVD Audio on the Premium Sound is distinguishable from the iPod input (iPod and USB adapter). I'm kinda thinking that it might be. Anyone know?
(The DVD audios will be created from my 7,000 iTunes tracks which are a mixture of 128 kbps and 192 kbps.)

DVD Audio is 5.1 encoded audio ... not a series of mp3's on a DVD although it does mean you can fit a lot more tunes on the disc !!!

so i understand right the premium package will play burnt dvd audio discs?

I assume so.. it should play discs that have mp3 content on them. DVD Audio is an encoded format... I am not sure how to burn DVD Audio discs.

u wud just burn like a mp3 disc but with more songs on it

I think you need to understand - DVD Audio is a special format as previously mentioned . I don't think you can simply copy MP3's to a DVD disc as that is not DVD Audio. DVD Audio is supposedly an encoded format (as previously mentioned) which has the audio already separated to certain channels based on the music playback. I have it in my acura as well and they give you a demo disc. It's like hearing the vocals through the center channel and then other music is mixed into other speakers...more like theater sound.

just from a technical perspective.. DVD format on a player means the unit can read DVD discs in addition to regular CD discs... DVDs offer alot more space for storing data...(in this case music files) MP3s can be written to blank CDs but you can also burn them onto a blank DVD disk too..(and you'll fit 100 times more music)

at the end of the day the unit will still play the contents of both discs...(just alot more music if it's coming from a DVD disk)

as for sound/music quality....it all depends on the recorded format, MP3 or other format you copy it to, and that format must be supported on the sound system unit itself...

I believe the X5 system supports only CDA and MP3 formats only.

DVDs also support music videos....but I don't think you'll be able to view them on the iDrive dash screen...

you can on the rear entertainment system...

Exactly: and from that point on it will depend entirely on the production of the recorded audio source. I have played some CD's on my E-53 and the sound was unbelievable while others sounded like garbage. Hard to believe but much of todays music is an atrocity from an engineering perspective. Hence the reason why many auto systems sound so bad. ;)