If you are looking for a cheap yet reliable bluetooth connectivity to H2 or H3 with XM radio, I have to recommend this:
H3 Quick n? Simple Auxiliary Audio Input ? Schwarttzy
and this:

Total is about $80'ish

Works great. Hands free telephone that is crystal clear.
The apps on the phone (like Waze, Google Maps, Music player, etc) all play thru the car speakers. And if you are lucky enough to have your phone to listen for "Ok Google", you really dont need to touch your phone at all

Oh, if you want XM back, just unplug the 3.5 mm connector and your back not normal.
*But why use XM radio when TuneIn Radio has 10,000x's the content of XM

--edit--
If you go this route, to make your vehicle sound even better, VIPER4ANDROID
http://vipersaudio.com/blog/?page_id=31
and a review of the app

 

You guys know that I now offer an option to use Bluetooth instead of 3.5mm headphone jack right?

H3 Hummer Quick & Easy Bluetooth ? Schwarttzy

 

Great stuff Schwarttzy