Interesting, Jcurtp24. You kind of confirm what I thought--the K900's performance is a bit sub-par vs. what you would expect from the specs.

The gas mileage thing is definitely not in your head, though. I experimented a good bit with all the drive modes when I first got the car, and I found there was about a 2MPG difference between Economy & Sport. I've since settled down to keeping it in Smart mode to sort of split the difference.