I think the dirtiest secret is battery performance drops in hot weather and especially cold weather. Also range is significantly impacted by having to run heat or AC. So the Tesla will perform best if you live in San Diego.
The $80K Tesla have battery heating and cooling to try and mitigate some of that. Not sure how well it works when it is zero or below..
I've read on blogs that lesser electric cars may not charge until the battery cools down. Or the battery won't quick charge, but will take a standard charge instead.