advice on FM cassette and CD player radio

I have always used stand alone units for XM. Currently have the XM Edge. Steaming through your phone, the quality suffers and you cannot use it when in an area with poor or no cell coverage. Also your listening will be interrupted while the thing "buffers" to catch up and of course incoming calls will interfere. For twenty bucks you can get an adapter that installs in-line with your antenna and basically cuts out the FM antenna signal and all the interference associated with it. I wouldn't drive with satellite radio.