I have the premium sound system and IMHO it is definitely worth the extra $$. The sound quality is so good that when I'm driving I feel like I'm in my living room listening to my home theater system.
2004 E60 530is, Delivered 12/12/03, TiSilver/LGrey, PP, SP,PS, PDC, ACC, FRS, Step, Xenons, clear bra, body colored rear inserts. (Retired, 1983 henna red 320is)
2004 Corvette Z06 Commemorative Edition