These newer HPs work down to near zero with a COP of 3 or better. Not electric strip heat. There is LOTS of heat in zero degF air. Its just that the larger the temp differential between outdoor and indoor, the larger the pressure swing on the refrigerant cycle. Oh and in a heat cycle, the outdoor coil is the evaporator, not the condenser.
Life of compressors is not an issue. Well made AC systems in Houston last 15 yrs without difficulty and they run 8 months a year. With July and Aug running 15 hrs a day. (if they are sized correctly). A replacement compressor is about $1500 to 2k either way. The point is, the compressor lasts just as long in air to air service as in ground source, its just a larger temp differential.
GS is more efficient yes, but at a MUCH higher install cost. GS can cost 12 to 15k a ton to install, if its even possible at the location in question. At our Durango house it would be over 80k for a 3 ton GS HP, and that would only supply about 60% of heating on a zero deg day.