I also live in NE and we recently installed a mixed system. We have mini split units in the upstairs and a ducted air handler in the basement all attached to a

I also live in NE and we recently installed a mixed system. We have mini split units in the upstairs and a ducted air handler in the basement all attached to a cold weather heat pump outside. It has be working great for us so far, but we have the advantage of having a smaller house so we only needed one 4 ton unit outside. Our house was built in 1973 and originally had electric baseboards and then was converted to an oil boiler with hot water baseboard. So retrofitting a heat pump was an interesting task.