A bit late, but maybe someone will read this. I live in Toronto and installed a heat pump this year. We've been through the worst of Winter, I believe, and although the cost ramps up on the coldest days, the heat pump worked perfectly at -15C (it claims a COP of 2 at that temperature). I watch the auxiliary circuit, that is triggered if the heat pump fails to heat to the required temperature, and it never ran for the whole season. Yes, Winter can still get a lot worse and a lot cooler, but my house also has insulation and there is no scenario where I will freeze to death.
In terms of cost, it's a lot cheaper than gas + electricity (it evens-out on the coolest days, and is cheaper otherwise). It will not amortize the cost of the heat pump itself for a while, but that's a cost I'm happy to eat right now.
In terms of cost, it's a lot cheaper than gas + electricity (it evens-out on the coolest days, and is cheaper otherwise). It will not amortize the cost of the heat pump itself for a while, but that's a cost I'm happy to eat right now.