I would like to upgrade my existing stereo, which is the "premium sound system" in my BMW 540i. I truly think this stereo stinks. I cant hear any of the highs or treble sound. The stereo sound completely FLAT!!! I was told that everything about the stereo would have to be ripped out except the head unit located within the front dash. Is this true? If so, what type of power amp and pre amp EQ would be recommended. Also pleae let me know about speakers, again, what type (name brand) should I get. when I speak with different car stereo dealer/shops thay all cut each other down including the products that they sell, telling me that their merchandise is superior to the other merchants "garbage" One of them is lying, i just cant tel which one. Please give me full details of your recommended car stereo equpment, name/model, model#, size of speakers, needed power for the amp, etc. Thanks so much to all that respond. Please E-mail me at: LEGALRESEARCHLLC@AOL.COM