My 2002 GTi came with the Monsoon system, so while this isn't quite as direct
an answer as you may have hoped for, I can provide a little insight. I
purchased and installed a high-end Eclipse deck prior to buying my amp and
speakers, and allowed the Eclipse to control the otherwise stock Monsoon
system. Although my deck is of high quality and I had a much more in-depth EQ
to tinker with, I found it very hard to make the stock speakers sound "right"
after the install. I can't verify this completely, but I believe that the
factory VW decks have some kind of active EQ in them, set specifically for the
factory speakers. I'd highly reccomend waiting till' you have cash for new
speakers till' you install the deck and amps. This, at the very least, will
help minimize your labor charges at a local shop. One last note, be VERY
careful about how you pick your tweeters, unless you plan on moving them to
kickpanels. The a-pillar "sail-panel" location that VW factory tweets are
installed in is VERY small, and that area required physical modification in
order for me to fit my Dynaudio tweets in properly. Crutchfield has a pretty
good fitment guide on their site. Using it may help you find a set of
components that will fit properly.
Steve Grauman