Replacing our upstairs system (2 tons) in our two-story 1960s era house in North Texas (hot, fairly humid in the very long summer, very little time when heat is really needed during the year - but it is needed every winter at some point). We do not anticipate living in this house forever - probably will move within five years.
OPTION A - Carrier Comfort 16 R410a, single stage
Condenser - 24ABC624A003 (single stage)
Furnace - 58PHA045-1-08 Boost 80 (single speed)
Coil - CNPVP3017ALA
OPTION B - Trane single stage
Condenser Trane XR15
Coil - Trane AHRI
Furnace - Trane XT80
OPTION C - Carrier Performance 2-stage R410a
Condenser - 24ACB724A003 (2-stage)
Furnace - 58CVA Infinity 80 (variable speed)
Coil - CNPVT3014ALA
OPTION D - Amana two-stage
Condenser - Amana 16 SEER Performance 2-stage
Coil - Amana
Furnace - Amana 80% Two-Stage, Variable Speed, 70,000 BTU
Thanks in advance for any advice you experts can offer! We understand the importance of good installation and these providers all have excellent Angie's list ratings (and lots of them).
Last question - how much difference in our electric bills will a two-stage versus single-stage system make in our climate?