Our first ACE, the 2012 is pretty noisy. Lots of engine noise, wind noise and road feedback. Our 2013 is quiet. No real road noise, the engine compartment is much quieter, we feel less heat from the doghouse, less road feedback (it does have slightly larger tires with lower psi rating) and much less wind noise. Exact same chassis and MH. Different years. Different floorplans but I doubt that has any affect. Point being, the way these things roll off the line, 2 identical coaches could be very different in terms of manners and noise.