equipment could be described as a box full of parts. the fact is that all the major competitors in this market use essentially the same technology. we contractors have our prejudices and are dealers of one brand or another, but to be honest, comparing apples to apples, the bells and whistles are all pretty much the same and the compressors and other parts are the same too. that said, i would suggest that you find a contractor who will modify your ducts if necessary to give you all the efficiency your equipment is designed for. air delivery and distribution as well as return air size are sorely ignored and overlooked issues. the cutting edge efficiency involves two speed compressor, variable speed blower and communicating thermostat. if you're going to invest for long term return, this type of next generation system is the best way to go. it is designed to be smart enough to control the humidity and the temperature through staging and ramping fan speed. the fan runs quieter and the power savings is significant. in my opinion, the difference in the price between this type of system at 16 seer compared with a 14 seer is worth it.