I took an interesting road trip this week in my Model S. Connecticut to Vermont: total distance exactly 200 miles. Charged the night before to maximum range and left with 263 miles range indicated. Trip was almost completely at highway speeds, and I kept the speed on cruise control at the posted speed of 65mph. (Note that this was unusually slow driving for me, but I was concerned about range at higher speeds. And, I must say, it was kind of relaxing just poking along in the right lane). As we approached the destination there was a long uphill stretch, and the miles remaining started plunging. About 1/2 mile from destination the display read 0 miles remaining and then "CHARGE NOW." Given that I was so close, I continued and arrived without problems at my destination. The only charging facility available was a 110VAC outlet. So I promptly plugged in and waited, and waited, and waited. 48 hours later it was time to depart. 117 miles displayed on range indicator. I'd been checking the range over this two day period, so the 117 miles wasn't a surprise by this time, but I had initially expected to get something approaching a full charge over a 48 hour period. This was a lesson learned. I'm not going to plan on ever getting anything like the 5 miles/hour charging I expected. Better to count on the 2.43 miles/hour I got. The trip home (with 3 charging stops) took 9 hours, compared to 3 hours in the other direction. Needless to say, the proposed Supercharger in southern Massachusetts would have been very helpful! To place this experience in context, I still love my S. I've NEVER experienced range anxiety prior to this as I wake up every morning with a full battery courtesy of my HPWC and never drive anywhere near 200 miles in a day. But this was a lesson learned. The planned Supercharger rollout will be very welcome.