It's a pain to replace a Bose car system. You have to replace the speakers, amps, and head unit. The amps are actually located near the speakers. The head unit is just a pre-amp.
And I agree, compared to many factory audio systems I've heard, I really like the Bose system in my car.
Was this an upgrade from a standard system?
I do remember a friend having a mid 80's Camaro with a Bose system(I think) and as has been eluded to, sounded quite good for an automotive system.
I have always gone for the cheapest audio systems as the extra cash can be spent on much better products in the aftermarket and it's a lot easier to remove a radio and speakers than trying to remove all the individual parts they stuff into the wierdest of places. I usually just wait till the speakers start to crackle then upgrade those first, then move on from there if I still own the vehicle.