I know that in Orlando, they have to use concrete blocks on the first floor because of termites. Is the same not true in your area? I would think that you would also want to have concrete for some protection during tornados.

I prefer concrete block. Strength and durability to weather and termite damage are just one factor. Consider the ground temperature in Florida is fairly constant, a concrete block house acts like a heat sink drawing warmth in winter and disipating heat in the summer. A well insulated frame house will only perform based on the heating and cooling that is applied to it. A well insulated concrete block house has passive heating and cooling characteristics.

Block is better, but be sure to specify an insulation board on the inside before the furring strips are installed to cover 100% of interior wall.