I just have a question for the pros out there:

If you were to pair a Trane 3.5 ton XR13 (or other single-stage heat pump) to a variable speed air handler, which one would it be? The sizes available vary. The sizes I could see pairing with a 3.5 ton single-stage Trane heat pump have capacities such as 40,000 BTU/H or 49,000 BTU/H, both of which would be ARI-rated matches. Which capacity would be better to go with 42,000 BTU/H? Have you had a match-up like this in the past? I'm just curious, as I've been wondering this for a while.

Thanks in advance.