I just traded in my 2004 Prius for a used C-Max Sel. It had 18K miles on it and the lifetime average was 35mpg. I reset it.... new driver and all and have some observances. I tried driving 57-60 mph and felt I was struggling to get 41-42 mpg (all highway miles). I drove 70 mph last evening as felt I easily got 44.2 mpg over 90 plus miles. I have only driven around 500 miles with the car so far. I think once I get the tires inflated to my liking and put some Mobil 1 0W-20 synthetic in I should be able to get around 45 mpg with little difficulty I am glad there is a good forum started. I thought PriusChat was an excellent source of information about my Prius. I am hopeful that this site, as it develops, be similar.