I have a 08 Mazda 5. Is this + the subscription all that I will need to get the wife hooked up? If so what is the $300 unit that I'm keeping hearing people talk about?

http://www.bestbuy.com/site/SIRIUS+-...ustomerreviews

 

The $300 package is the Mazda kit that you would purchase through the parts/acessories dept at your dealership.

The product description in the link you provided states it works with most satellite ready radios but I'd guess that may be directed more towards aftermarket head units. I'm sure Mazda uses some sort of proprietary connector to make you use their kit. Maybe give Sirius a call to see if they can tell you if this kit would work with the Mazda's stock radio?

If you end up going this route please let us know what happens. I just took delivery of my used '06 and want to add Sirius to mine as well.