I'm in the Portland area and got a heat pump installed in 2021.

I overbought for sure, as I got a hybrid system that has a gas furnace backup. I've never needed it, but I've had a couple times where I wanted it and it was nice to have. If I switch it from "Heat" to "Emergency Heat", then it overrides the automatic determination of which heat source to use and just uses gas.

I didn't lose power during that cold snap, but if I did, it would have probably brought the temp back up in under 4 hours.