I have and XM Radio system in my 400H. My son put it in for Fathers Day. I was also disappointed that it wasn't pre-wired for XM. For all the time it took to get to market, they could have done that. It isn't a pretty set up, He did a good job hiding the attenna wire. I have a velcro patch by the shift console. I was using the FM adapter, but the there are too many FM stations in the Washington, DC area so I have gone to the tape adapter. I have the Roady 2. I will brinbg it in the house and overall I am pleased with the set up.