I have estimates for replacement of my furnace and A/C from two local contractors. One quoted me Carrier and the other offerred me York or Armstrong. The carrier estimate was exactly twice as much as the York/Armstrong. I am thinking the Carrier is better equipment but not worth twice as much. Am I wrong? Given the choice of York or Armstrong for the same price which would be best value assuming comparable equipment? I didn't get model numbers yet but the quote is for a 4 ton 12 seer A/C with an 80 per cent efficiency gas furnace. I have a 2200 sqft single level house. All advice appreciated.