it's the common question here: what heat pump system to get. We have a 2400sqf two-story house in Maryland, northeast of Baltimore. No shade and southern exposure, but I sealed the duct trunk in the (unfinished, fullsize) basement and return "ducts" (no sheet metal, just drywall and framing), airsealed the basement and the attic quite well and added a good amount of insulation into the attic (which has saved us already considerable amounts of money on our energy bills). Manual J calculations will be done according to one of the contractors visiting so far, as required by the county (is block house load calculation the same?). We haven't received his estimate/recommendation yet. After reading many posts here in this forum, we lean towards the Trane XL20i with matching air handler. Any reason not to go with that over a XL15i or XR16? The XL20i is the only two compressor system which gives it a slight advantage, short of the Carrier Greenspeed. What the difference between the TAM7 and TAM8 airhandlers? The Trane website is short of information on that. Any recommendations for a thermostat and media filter cabinet? We'd like on-demand dehumidification, which why we don't consider the XL16i. Recommendations/thoughts with regards to a whole-house humidifier? What about Carrier? I know they don't have on-demand defrost which might me quite important in our climate. No Rheem/Ruud dealers in the area, and not too many York either. Does York have anything comparable to the the XL20i or other features that might be important to consider. I tried to read as much as I could and I know some of these questions are redundant but the search feature gets you only so far.