If you have an iPhone, if you get the Tethering Hotspot option from your cell provider, you can run Entunes via BT. The extra $30 was worth it to me. Makes it totally hands free. Don't even have to have Entunes running on the phone.
I think I read or heard somewhere that the Advanced model uses BT but you are supposed to use the USB with the Base. The tethering approach is an effective workaround but costs additional from your cell phone provider.
This, of course, depends on your provider. In my case, I don't have to pay anything extra to use tethering with T-Mobile on my iPhone 4S.
