I have a 2003 VW Passat wagon with a factory installed Monsoon stereo system. The head unit is just a generic CD/Tape deck with AM/FM radio, but doesn't have satellite radio or mp3 playback capability. I am looking at possibly getting a JVC head unit that offers both of these missing functions. I have a plug-n-play satellite I have used in the vehicle. Also, I have used an mp3 player with cassette adapter, but I want everything neatly in the dash. Therefore why I am looking at an aftermarket stereo.

This is the unit I am looking at getting:
http://www.crutchfield.com/S-nDOFmuu...p?I=105KDDV530

My question is this....The current monsoon sound system sounds great & I plan on keeping the original speakers installed, but will I lose sound quality by replacing the factory head unit with the JVC aftermarket head unit? Is the original VW installed Monsoon equipment better matched than if I switched out to a JVC unit?