Switching to Electric Heating

I went to the Ontario Hydro calculator to look at switching from oil heating to electric (natural gas not available here). This calculator says that I can save about $400 per year by switching. I have much doubt about this. Has anyone actually done this switch? Do you believe this?

Edit: some more info I should have provided:

First of all, I believe this would be for a forced air electric furnace. This should easily swap in for my oil furnace, I would just have to add a 220 line.

I live in central Ontario. I don't have or need/want air conditioning, so there is nothing to save there.

I am not sure about a heat pump for my case, since it would not be used in the summer and they become less efficient as it gets colder. I am not sure I can rely on a heat pump as my only heating source.