Soldato
The stock speakers/amp are very good on e39/e46, it's the stock head units that are crap. I have just an aftermarket HU in my car and the sound quality is better in orders of magnitude compared to stock.
I know the stock headunits are dire but I am interested in how this solution compares to other aftermarket headunits in terms of sound quality (hence wanting to know the overall setup - speakers/amps etc to get a better overall picture)
I have a reasonably good Pioneer headunit and Rainbow 6.5" components up front in mine and I'd be hesitant to change my current headunit for one such as this if it meant taking a significant hit in sound quality even if the navigation etc was excellent (I appreciate it is all subjective, of course)