Had ours less than a week but we are already showing 44 & up mpgs, displayed on the screen mind you. Wife did a 26 mile run yesterday on rural roads, ac on 76 & got 47.6. I believe the differences are mostly weather related. I own some Geo Metros & belong to the geometroforum.com We also discuss many different ways to increase our mileage. Grill blocks, adding air to the tires, aero mods, total removal of ac systems, etc. Cold weather totally robs those cars of mpgs. Typical loss of 5 to 9 mpg in winter with winter blend gas is not uncommon.