I only have L1 / 120V charging at home. Have never used any other charging method for my Nissan Leaf, which I've owned for two years. I have a 20 mile (total) commute, and really only charge every other day or so. I've never reset the efficiency calculator, and the average report is 4.3 miles/kwh. I don't think I really engage in any hyper-miling behavior, but I might drive more efficiently than most.