$400 electric bill traced to heater - what could be wrong with it?
From the DFW comment, I'm guessing you implied Dallas/Fort Worth. If that's the case, then you'll have AC already installed, and a lot of winter days that are above freezing. For that climate, a heat pump would be much more efficient. The emergency heat setting on a heat pump is the same as what you already have and you'll want to use that when it drops below freezing. But all other times the heat pump will be more efficient.