Only the BMW Com System headsets will allow you both to synch to the bike's onboard radio, and allow the rider to control volume using the Scroll Wheel.
The SRC system can be synched to two different music sources for rider (bike) and passenger (her own phone).
The Sena 20S headsets can share music, so the rider is connected to the bike, and the passenger is connected to the rider's music and intercom.
The GPS directions come through the bike's radio, so they'll work with whoever is synched to Helmet 1 on the bike.
Bluetooth synching to the GPS is done to allow for phone control, not for music or directions.
Ken IBA# 366
'13 Dark Graphite Metallic K16GTLD
Some people see the gas tank as half empty. Some see it as half full. All I care is that I know where the next tankful is coming from . . .