I have an '07 BMW 530i, and the AWD is more than fast enough for me, but I couldn't justify the extra 11k, although the lifetime supercharging did temp me. I would have definitely done it for 6k though, as supercharging alone would be worth it. I only charged my M3 once via the 110v charger and have had it at the service center & Body shop for the last two weeks (chip on bumper and corrosion ynder hood spacers on delivery). Currently driving the S 75D loaner and really diggin' the ease of supercharging, especially when making the trip from L.A. to Vegas.