I have noticed that many new houses being built in my area are getting a gas unit installed in the basement for the 1st floor and a heatpump in the attic for the second floor. It has been my experience that builders will install options that maximize profit vs what is best for the homeowner. Can a single larger gas system using zoning do as good or better than a dual system. I have had a heatpump in my last two houses and have never been comfortable in the winter. I simply don't want a heatpump.
I know that many people say a properly installed heatpump can be just as good as a gas furnace but I don't agree with them. I live in the Baltimore area where it often gets down to below 10 degrees. I just find the gas heat more comfortable.
I am planning a new system in my house which is 3000 square feet and 3 levels. I want the most comfortable system I can get not necessarily the most cost effective. I am willing to pay $20 or $30 extra / month to be comfortable if thats what it takes.