Well, I own an '06 AWD FEH. My normal commute is 44 miles one way, 41 of them on the highway at 65 miles per hour. (Cruise Control) During the summer, I was getting 34+ MPGs, and even now in the cold and wind, I'm getting 31+.
However, that's for my commute and there's other driving involved at times. Your milage may vary, especially in light of your last post, unless I'm not understanding you, it's a 3 mile commute one way. With a commute that tiny, it probably doesn't matter what you get, you're going to get crappy MPGs, as there's insufficient time for good warm up to optimal use and FE.
I'm surprised Delta, I would've expected you asking if the wife really needs that much vehicle, since I am.
Is there a reason she needs a large vehicle for such a small commute?