I recently bought a foreclosure that is a post WWII home. The home has a naturl gas fired central furnace that will need to be replaced soon and the A/C cond. unit outside was installed in the '70s. We insulated all of the walls of the house and the attic has about 16 inches of a combination cellulous and fiberglass blown in. I plan to replace the double pane alum. "not too great" windows with a higher performing vinyl. I live in North Arkansas where we pretty much had no winter this year. But, some winters bring ice storms, snow and temps below 28 degrees. QUESTION: should I get a heat pump or a natural gas fired furnace when I take the plunge??