My salesman rocks... we went on a "real" test drive with my 2.5 yr old girl (in her britax car seat, middle position) and my wife in the backseat, sales guy and I in the fronts. He took us down a fun gravel road, had us explore the washboards and try full antilock stop on them, then had us turn right across a big ditch and into a field. Then we put on 4L/lock, and went up and over a big earth levee at max approach angle (mud in the trailer hitch to prove it) followed by DAC down the lesser angled side.
My little girl loved it - she was laughing and cheering from the back seat. Mom was a little wide eyed but I have a DC TRD OR now
Later in the parking lot, we also tried out the Graco 3-1 booster seat (the spare, that will become her big girl seat when she is big enough) to make sure it sat ok back there too.
I highly recommend taking the car seat(s) and trying them in all positions and with adults in the front and back seats too... this is gonna be the family wagon from day one (my prediction, based on my results). Enjoy!