In Seattle are highest usage months for electrical is in the winter, right when you will be maxing out that 50A breaker you had to install in order power that beast; check the notes from Mitsubishi, they are clear that it is not an efficient device in the range you suggest ( and seeing how in Seattle most homes are still at 100A service you must either be living in a newer home or one with an upgraded service ).

You realize that Seattle is now an importer of electricity and is no longer running surplus?

Or how about that the city has been using an unsustainable amount of water? ( i.e. where our power comes from ) Or that our electrical come at the expense of Salmon and the endangered Orca pod that lives in the Sound?

If you replaced your "furnace", which implies a central HVAC system, with a Mitsubishi Hyper-Heat, which I believe is only installed as a mini-split, what are you doing about your air quality?

The Seattle area suffers from "inversions" through out the year; a mini-split does nothing for air quality issues. The smoke that we dealt with in the fall? That wasn't even the worst air quality issue we have had in the last decade.

I am sure your electrical bills are 1/2 of what you were paying for an electric furnace, but unless you are abandoning the use of your heat pump for providing cooling your overall energy yearly costs are unlikely to go down.

I don't know situation, I don't know what options you had when you installed your unit, and I have not listed all of the good and bad that come with the unit that you installed.

There has been a lot of "mini-splits will save the environments" coming out of our City Council; there have been zero reports presented that back up those statements. The local heating and cooling people are happy to install units which have a higher markup/generate more work for them.