Sirius or XM. XM or Sirius. It doesn't matter what side of the fence you sit on, Pacific Stereo has the upgrades you need to deck your car audio system out with Satellite Radio including Sirius Packages, Sirius Tuners, Sirius Adapters, XM Packages, XM Tuners, and XM Adapters. Pacific Stereo ensures you are never left stranded in outer space when you need help - your Satellite Radio Store purchase is backed by our 30-day money-back guarantee and the manufacturer's warranty.