I am about to buy a house but the owners are to replace the furnaces (2). I live in the southeast and the repair/installation company is planning on installing a 80% efficient Bryant Furnace. They said that there was not really any need to upgrade to a 90% efficient model unless I just wanted to spend the extra money (we have to pay for the upgrade, but not the replacement). Is there anything I should know about Bryant units? I heard 80% effecient units are fine in milder climates. Are there any other thoughts on the subject? Thank you.