Yes, using Aux-in you can listen to an XM radio like the Roady 2 through your radio and use the steering wheel controls for the volume. I did it on my 2004 but got bored with XM, found that a thousand songs on my iPod in shuffle mode had the same effect but $10/mo cheaper.
If you get Sirius from MB then you can see the song name on the dash and radio and change streams from the steering wheel control but it's about $1K installed.
You can get tired of certain channels on either sat. radio company depending on their format. I usually listen to Ethel on XM, which is mostly current alternative rock. Most of the music I hear and enjoy on that channel I would NEVER have known about before! If you never want to hear new music and you enjoy hearing the same songs over and over, then stick w/ a CD changer, an Mp3 player or get Sirius. Several XM channels have MUCH deeper playlists for people who want to hear new music or old music that is "new" to you . I have ordered the cable for the standard radio in my '05 C230 sedan so I can access it's auxillary input for a $100 XM Roady. I'll be mounting the Roady where the ashtray and lighter currently are. The antenna will either go on the front or rear decks.
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