Hi Brian

I just purchased my HCH about a little over a week ago and have 700 miles on it so far. I have filled up twice at the half tank mark and the first tank manually calculated out to 39, and the second one at 37. I am about the fill up for the third time and it appears I am getting better gas milage as my computer show 37 where before it always showed 34. So like you I am waiting for this magical moment to surge to the 40's or better. I live in Florida so I have to run the a/c which as you have read can make a big difference in the milage game. We will have to just sit back and wait and see what happens as the car breaks in!