Let the hive mind of Engadget get that for you.
"I am looking for a device that will stream sound from one source to several recipients. For example, I want to stream sound from my TV or stereo to my phone or MP3 player that has radio and Bluetooth capabilities. I have looked into radio transmitters and they seem like a decent choice, but I can't find one that uses external power (USB or from the plug) and I would want one with a transmit range of around 50 meters. Thanks!"
But to get back to GM, its not like Lexus reminds anyone that its a toyota marque, and I don't know how many times my dad has forgetfully asked me if infiniti is a Chrysler brand (?). the japanese market in a way to have their brands stand on their own, and its seems to work well for them.
I'm just gonna finish with saying that it seems that having GM on everything is sorta condescending to the consumer, suggesting that they can't figure out what they want on their own.