When I buy my used Volt, I want to know what percentage of the driving was done using the ICE & what percentage was EV only. This information should be multiplexed with the odometer display. Maybe you push the little button and get the trip odometer, and then you press again and you get the EV-only miles. The two modes stress different parts of the car - EV mode cycles the battery, whereas ICE mode does not cycle the battery. If you think that the battery will last forever (A123), then you would want a car with a lot of EV miles. If you think that the ICE is more reliable, you would opt for more ICE miles. I believe that there will be a thriving market for used Volts & the %EV data would be very relevant.