Well, I'll admit, the last two years have been a bit dicey...and unusual...considering the low temps and heavy snows. Typically we don't see anything below freezing very often, but now we're seeing lots lower than that and it sticks around for weeks.
If next winter is a threepeat, I'm replacing my second-level heat pump with forced-air heat and refrigerated A/C like's on the first level. That upstairs aux heater to augment the heat pump during these prolonged cold spells is tremendously inefficient and has been adding an additional $200/month to my electric bill.