Heads up for E70 owners
If you use the BMW charger with the cig lighter input (as I do for my Z3) it won't work on the E70. The cig lighters in the the main cabin are switched off with the ignition. If you're going to store the car, you'll need to get the charger with aligator clips and attach to the studs in the engine compartment. Minor issue at most, but something to keep in mind if you leave the car for a week or so.