Hi folks! I know very little about Sirius/XM radio and need some advice. My Father-in-law loves his Sirius radio and uses it both at home and in his truck. He'd like to install a docking device in his boat. My wife and I would like to buy him the best device for installation in a boat for Christmas and I'm hoping you experts might be able to give me some guidance with this purchase.

Thanks, I appreciate any tips.