New BMW radio upgrade

[tsperez@xxxxxxxxxxxxxxxxxxxxx]

My son is about to receive a new 2002 330Ci in a couple of months and the
first thing he wants to do is replace the radio/CD player with a unit that
he has that cost him about $500.  He likes it because it plays MP3 recorded
CDs and is rather sophisticated (in features).  
Is this a wise thing to do?  Can the unit be installed without messing up
all the wiring behind the dash?  Will it match the existing 12 speaker
system that the car has already (including two sub-woofers)?

Thanks in advance for any advise.
Tomas S. Perez
540i, 325is, and two others.

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