Heat pump mode augmented with furnace, or some other type living space heat?
Single hose would definitely outperform.
On the other hand these is a great deal of confusion over the "heat pump" term when applied to the low end A/C market. In COLD weather a 2 hose A/C heap pump, reverse refrigeration cycle, would NOT match the performance of single hose A/C heat pump. Like those new "heat Pump" hot water heaters when installed inside the living space, the single hose unit would operating "parasitically" from/off the axillary heat source.
That's why those new heat pump water heaters should NEVER be installed within heated living space.
Robbing Peter to pay Paul, as it were.