I live in NC and have two Goodman A/C split system units 2.5 ton and 3.0 ton for two story at about 3100 sq ft. I asked our A/C guy to drop me a price quote on new units and would like to look for something more efficient. He recommended I just stick with what I have which was put in (builders units) when the house was put together..."they still make a similar unit". I know there has to be something better since the house was built. I think its a 10 or 12 SEER and when I get home I can look up what I can to post later. I want to try to push for a higher SEER. I know the upfront cost is more but the return on monthly energy cost should be better right? I am open for getting a few more quotes but I wanted to give this guy a chance first since he has been there for us when the other units were struggling to get to the next season. Does anyone recommend a level to shoot for? Cause I am sure after a certain level its not that much of a savings due to cost. Tks.