I am in the process of replacing a 35 yr old furnace and adding A/C. I have discovered conflicting opinions on one issue. One contractor informed me that a modulating furnace or a single stage furnace would be best for my 2 story (2,000 sq ft) house. He said a 2 stage furnace would result in the farthest upstairs rooms being colder and he actually recommended the single stage unit (cheaper). I found another post on this forum that said a contractor recommended the opposite. It seems to me that with the narrower temp band of these new thermostats, a single stage would cycle a lot more with shorter run times. More start/stops = more wear, right?

Anyone have some thoughts, advice, input, etc.?