Manual J test shows a 4 ton unit for my home. I live north of Dallas and have a 2000sq feet home. My home is tight and has high celings. The difference in price is not that much. I want to purchase the best system to cool my home and remove the humidity. I thought I read once that the 16 seems to remove more humidity? Any thoughts or which route I should go? I will also replace all the ducts and add another return.