Winter is only ~20% for a given speed (give or take), unless you're compacting snow (then it's complicated based on the snow's density and thickness). Slowing down (which you should do in the winter!) has a much more significant impact on range.
Before you add any options at all onto the Model 3, you have to bring the BMW's price up to ~$42-43k just to match the base $35k Model 3. That's $35k *without* tax incentives; if you get, say, $3750 in the US (not counting state incentives) then then Model 3 is $31250 base. Here in Iceland, EVs are exempt from VAT, which is a quarter of a vehicle's purchase price, so it's even more major And depending on how much you drive and your local gas prices, operating the vehicle will save you $1-3k per year.
So go on and add the long range pack. You still come out way ahead. As for me, I really don't see much of a point to more range (although I might be tempted into it for longevity reasons, or - if Tesla comes to Iceland - supercharging rates). My speed limit is 90kph (56 mph); driving the speed limit here in local summer weather conditions should give something like 300 miles range, due to the strong correlation between EV speed and energy consumption. Up to 5 1/2 hour long drive times. I mean, who needs that?
