Incompatible receivers for Best of XM.

[sun622]

I have a Clarion Calypso and just found out that i cannot get the "Best of XM. I'd like to keep my connection the way it is and purchase a new unit that gets it all IF I can find a Clarion unit that will just plug and play. I have cruised ebay looking and none of the units indicate they are "Best of" capable. How do I know if they are??