Just purchased a 2007 B7 A4 with the RNS-E Nav unit, it’s got Bluetooth telephone functionality but I really would like the ability to play music via a Bluetooth adaptor

There’s a few options around by the looks of things, but how do they all compare? I don’t want to pay ridiculous amounts but I also don’t want it to affect the OEM functions of the headunit (Can take or leave steering wheel controls)