My hodgepodge of technical notes includes Amana ASZ16 heatpump at 34,400 btuh for 3.0 ton size, if I read it right. The Trane XL14i heatpump at 33,800 or 31,800 btuh. The Trane XL16i heatpump at 33,200 to 32,000 btuh depending on coil and air handler.
One possible reason to choose a heatpump would be not just by capacity ("bigger is not always better"), but by efficiency or performance around your actual climate conditions. I don't know enough to say whether any Trane models look better that in that respect. For a 2-stage unit, there would be long runtimes at low stage most of the year, though I am not sensitive to how valuable that is in heating mode. This is interesting to me but since I am in S.Texas where nearly every furnace is oversized, mainly of academic interest.
Thanks -- Pstu