I've just bought an 09 plate A3 sportback that has a double din chorus stereo. I've been googling for ages trying to find out my options for upgrading but most of the info seems to relate to concert or symphony units. What I want is bluetooth (for talking, not music), ipod connectivity and possibly sat nav. I don't have a multi-function steering wheel or driver information system, so presumably this will make things a bit less complicated. I'm happy going with an aftermarket unit if it makes things easier. Or if I go with a rns-e unit will it be plug-and-play? Any advice would be appreciated.