I have a 2014 X3 35i
No problems here in chilly Colorado. Temps are warmer now, but before Christmas we were seeing some temps below 0F. Not as cold as you all in the upper states, by ANY stretch, but cold enough to count for something
No probs with the heater. I keep it set at 70F and make sure the vent on the dash and rear seating area are set to the RED end. Fan is on auto and the speed is set to max. If you don't set the speed to max and auto, you never get full force from the fan and air does not circulate well. In auto mode, the fan speed determines the maximum fan speed that can be used in auto mode.
Car does not blow any air when I first start the car. Not until it warms uip a bit. Very considerate
After 2-3 miles at 45 mph, I start getting some decent heat from the vents. Of course, I have the steering wheel warmer and butt warmers on full roast from the beginning
Makes the warm-up wait for the heater bearable
In certain conditions, I have to manually direct more air to the defrost outlets, but usually I leave it on auto for the outlets, too.
BTW - same instructions for air conditioning, except make sure the vent dials front and rear are on the BLUE end.