I just bought a '97 528i (with the "premium sound system")and agree with most others that it is lacking good sound. I do not want to spend tons of money, and probably do not want to invest in the A/D/S aftermarket upgrades. My main concern is the rear speakers (totally muffled sounding) and bass. I can live with the factory decent highs and sound from the front, but the rear sound sucks. Any opinions on replacing the rear speakers with something more "full-range", adding a sub (trunk placement?) and running a tri-mode amp, tapping into the rear speaker lines...2 channels stereo to rear, 1 channel bridged mono to sub. I did this in an Acura Legend and it turned out great. Thanx!!!