I am buying / building a house in orlado and have to decide between a 12 and 13.5 seer unit. I have a couple of questions. If I go with the 12 I can get R-22 or Puron what are your recomendations? There is a considerable price jump to go from the 12 to the 13.5 which seems odd as the efficency is not that much more. The 13.5 does come with a variable speed AHU and programable thermostat it just seems like the payback time will be pretty long to me. Or will the added ability of the variable speed AHU to remove humidity here in Florida be where the payoff will come. Any thoughts would be greatly appreciated !!