I'm looking for a unit that will be double din and have XM, aux, USB, MP3 CD. I can find all the others but XM in about every radio, are all of these radios just incompatible with the stock XM setup in the Cobalt?

 

yes. most radios are xm or sirius ready but your not going to find one that uses the stock xm (not really an issue with the radio itself persay but ya long story short just not gonna happen)