Interesting, I don't know anything about either of the things you mentioned: range mode (When giving me the car, they told me it could go about 200 hours on 1 charge but to keep it under 150 because if it got completely drained I'd have to pay $10K for a new battery. Most of the time I would hook the car up to those free chargers in downtown PA), or not speeding (I always assumed speeding was good for mileage. It's also easier for me to speed in a tesla bc there aren't engine sounds, just road sounds, and everyone speeds on the 280).