Hello all,
My wonderful girlfriend recently purchased a used 2005 xA with a "satelite ready" pioneer radio. She commutes A LOT for work so I decided I want to surprise her with the gift of satelite radio.
My question is, what do I have to make this happen? From my basic research, I'm probably gonna need to buy something to make the "satelite ready" radio into something that is actually ready for satelite. As I understand it, it is an antenna kit of some kind. So here are my questions:

1) Which one specifically would you recommend for the cost conscious (aka nearly broke) college student? (In other words, which kit is the cheapest that will work; urls are appreciated)

2) Is this something I can do myself AND make look nice and clean? Or will she rip my head off because there are a bunch of cables now lying around (I have some experience changing out car radios) How involved/how long will it take?

3) How can I tell if her car is already to go? Remember it's a used car, so is it possible the previous owner installed it? can you tell just by looking at the car?

4) This one might open up a can of worms, so feel free to ignore it and focus on question #1, but I need to ask: XM or Sirius? Why? (again, #1-2 are more pressing issues to me at the time)

Thanks to everyone in advance!