I have a 2007 Legacy Limited. On the stereo selector, I have a button for Satellite.  Does anyone know if it is ready to go with a subscription or do I need additional equipment to get the signal?

On new cars, Subaru might include a free short-term subscription to Sirius. E.G. only 6-months.

After that you have to pay.

Satellite radio?? Wtf? 

I’ve never heard of this in an everyday use vehicle. Digital radio is becoming a thing here in the major cities but that’s in development still and is a free service. 

Why would you want satellite radio? 

Cheers 

Bennie

I've heard that cross-country travellers, like truck drivers, love satellite radio.

They can listen to the same radio station all day, even as they get out of range of terrestrial stations.