The Daikin US7 was the first split system heater/air-conditioner in the Australian market to achieve a 7 star energy rating.

For the Daikin US7 2.5 unit, 2.5 kW coolth / 3.6k W heat, the Coefficient of Performance (COP) is 5.9 (or 590% efficiency). Which means for 1 kWh electrical energy, you get 5.9 kWh of useful heat/cool. 

As a comparison a gas heater is only 80% efficient, so for 1 kWh of gas energy you get 0.8 kWh of useful heat.