Yes, you can have traffic and not music. Check out the SirusXM site
for details or give their customer service (good luck!
) a ring.
MBZ is not the only company that charges for map updates. Lexus and BMW do the same thing, as do many, if not most other car mfgrs for their Navs. The auto mfgrs don't own or really manage the map data, most that I know about come from Nokia and NavTeq, I believe who probably have a royalty that needs to be paid when updates are provided. I participate in 3 different Lexus and MBZ forums (and formerly 2 BMW ones), and this map updates charge thing is debated often in each -- always with the two camps -- one that will keep the mfgr Nav for what they provide beyond just navigation/maps and enjoy the overall integration with the vehicle even if there are some compromises, and the other that will figure out how to use their Tom-Tom, Garmin, or Smartphone as an independent device riding freely around in the car or attached via some device to the dash, cup holder, or whatever.
As to traffic data -- I think it comes down to how a mfgr chooses to implement it with their Nav. MBZ, Lexus, and others use SiriusXM Traffic to provide that info here in the US, hence there is a charge to SiriusXM for the service after the trial period ends. My previous BMW 335i used free FM-based traffic information that some
FM channels stream in parallel to the music channel, so while I would have had to pay for map updates when I wanted them, there was never a charge for traffic. Lexus has just announced implementing the free FM-based traffic in one of their new models vs. using SiriusXM Traffic. With MBZ beginning to implement Siri connection and other Apps with mbrace2, perhaps we'll see a change away from SiriusXM Traffic in future MBZ model lines as well. Only time will tell.