I'm looking to buy an F30 3 series and would like to understand the capabilities and differences between the BMW Professional and Business navigation systems. One key feature I'd like from previous use of Garmin and TomTom portable satnavs is the ability to reroute when traffic delays are encountered; do the BMW systems offer this feature?
And if so I'm interested in some more of the technicalities please e.g.
- how often is the traffic data updated?
- what source of traffic data is used? FM or DAB TMC perhaps?
- how accurate is the traffic data from users' experience?

Looking forward to receiving some replies to help towards determining this aspect of the spec for my new car.