XM... I have Sirrius satellite radio as well.... I thought that was a given though!

Matt,
The 6.0 L in the F-250 is plenty of power. Have you driven a F-350 many miles? All of my work trucks are 350's and they will beat the crap out of you if you go many miles. Make sure and get the King Ranch package if you do get the bigger Fords. It is like riding in your living room.