One big difference between siruius and XM is there subscriber count. Sirius has about 30,000 and XM has almost 3,000,000!!
I just got done ripping my XM out of my 94 Chevy and put it into my 99 Ram I just got. I ran the antenna wire thought the back window and up through the edge of the headliner. I have a Pioneer head unit that has a AUX input so I ran a dedicated line from it to the XM to get the best sound. I mounted the SKYFI on the center console right next to the 4x4 shifter. Sound is unbelievable!!!

I had to go 3 days without it when I first picked up my new truck, and it really made me remember why I pay 17.00 a month for my wifes and my service, FM radio really !! There is nothing better than driving 8 hours and never changing channels or hearing a comercial!!

I have had it for over 2 years now

Chris