Road noise: I have no frame of reference vs other vehicles in the class because I haven't driven any of them. In my opinion, the car is quiet yet still engaging to drive.
Acceleration: Not burdened at all. In fact, versus the previous CX-9, the turbo4 has quicker response because it's not searching for gears and a majority of the torque is available at low RPM.
My friend averaged 22mpg on the first tank of gas in a car that was literally right off the boat with AWD. I'm assuming as the engine breaks-in, the mpg will move up slightly.