I don't understand it when people say, "didn't even notice the trailer." I've towed literally 100s of thousands of miles in dozens of trucks with every kind of trailer and if I have a trailer I notice it. Even a 2000lb cargo trailer you can feel with a 600hp truck. Or at least you should be able to feel it or something is wrong.
About the truck, a good friend bought a new 3500 high country the other day. It is an amazing truck. Pulls really, really hard for being stock. Congratulations on a nice rig.