I am sure you audiophiles will pull your hair with this question, but anyway here goes....
I had HK premium in my 03 330Ci and although was happy with it, didn't feel that it was worth the additional 1K or so when I got my X5.
The X5 stock stereo is OK (and I just hooked up the hardwired i-pod)
, again not being a real audiophile, question is what is a quick/cheap addition that I would find some noticable improvement .......someone recommended addition of a sub? Comments? (Ridicules?)
Thanks much