I just heard from a customer in central Indiana. I did a 4kwh Enginer install in his 2010 Prius in December. He reported that just completed his second tank of gas since the install. So far things have been trouble-free. Results: 1st tank - 81 mpg 2nd tank - 87 mpg He has a ~30 mile commute on rural roads and a some city streets and the system lasts him almost the whole commute. He is a conservative driver, but does not use any special hypermiling techniques or have an engine block heater. He does have a garage at home. Can't wait to hear how things go in warmer weather.
