HI-V system are more expensive, and lower SEER. For the higher cost is that there is a low demand on these, and how the system is made.
SInce this is a new house going up, go with a regular A/C system, they are able to have room to work in adding duct work for A/C.
I think I only came across 2 Hi-V system. When I was in the field, we did the regular system.
wyounger- Air to Air heat pump in MN is not worth it, it's too cold in the winter for it. MOstly Nat Gas around here. As long the owner gets the outdoor sensor on the boiler, it will run pretty cheap.