DO NOT DRIVE IT as it's going to cost you a bunch. Once you've driven a coach with tag you'll never have anyting else. It probably has a switch that lets you take the pressure off the tag for better turning in hard turns. Mine actually raises but unless I'm making several hard turns I do not worry about it and I'm paying for the tires. Even if you forget to turn it off mine will go back down once I get into 2nd gear.
*It's easy to oversteer a long wheel base rig. Give you steering inputs a little longer to take affect and on a interstate see how little input (actually only a little pressure) will keep it between the lines... with practice you'll be surprised how little it takes.