Apologies if this has been discussed to death, but I couldn't find anything definitive with a reasonable amount of searching.. What's the general consensus on the accuracy of EVTripPlanner in comparison to the in-car estimation in the Model S? I ask because the one and only 'long' trip I've done so far differed quite considerably between the two. The car estimates pre-trip of percentage remaining at destination and and the end of the round trip came in within a percent or two (and I didn't drive entirely at the 'proper' speed for the roads that it would have used in the calculation). The actual usage reported was just over 20kWh in each direction. Yet the planning I'd done with EVTripPlanner for the same route had indicated only about 17kWh in each direction, a pretty substantial difference in percentage terms. As far as I'm aware I accounted for all the variables in EVTP correctly, yet the result was not as accurate as I'd expected it to be from what I'd read about it, and far enough off the actual usage to be a worry if I tried to use it at all close to range limits. Have others found this at all? Is there something I'm missing perhaps?