I was looking at the cost of the XM radio option in a new accord on the hondacars.com site. I was shocked when I saw that the price is 3.00 and about 850.00 installed! I went to Best Buy and you can get a whole XM system installed for about 0.00. I even looked at some small neighborhood locations here in the North East and some were having specials for 0.00 installed, which includes the satellite unit, antenna and dash board receiver, plus the installation. My question is: Is the Honda XM unit really that great and better than an aftermarket unit that they can charge double or almost triple?