I'm in the Boston suburbs and mine did OK this winter. The range seemed to be slightly down on the window sticker, but for part of the winter I was only charging to 80% anyway, so not a well controlled experiment.
The heat pump & resistive heater warm the car better on my 7mile commute than the heater matrix in my GTI used to, especially coupled with the fact that I can remotely heat while it's still plugged in before I leave the garage.