I have been driving my C Two in "normal" mode for the last two tankfulls and I've been in the low to mid 50's around town with the occasional inroad into the 60's shown on the dash display. I'm very happy with this... I filled up last night and decided to try ECO mode for this tankful to see if my numbers would increase. I realized on my drive home from work (I go home the same way every night) my indicated mileage was considerably lower. Could not get out of the mid 40's. Needless to say, I'm back in "normal" mode. Can someone explain this?? Not making any sense to me. I'm trying to drive as I have been normally... Any insight will be appreciated!