Firstly the US7 and other AC units can't really be compared one-for-one on efficiency alone. Most AC units are forced air heating devices while the Daikin US7 is a comfort solution. That's what sets it apart from all others along with being the lowest cost to run / lowest energy consuming air conditioner / heat pump on the market.
The reason it's so much better for comfort is that it includes a built in humidifcation unit valued at $500-1000 which harvests moisture from the outside air.
In addition it emits fresh air rather than recycled air so you can fill your house with fresh filtered air rather than progressively more stale air. Also, the way it distributes air by drawing from the top and bottom of the unit, as opposed to just the top, reduces air disturbance in the room (being blasted with warm air is not ideal).
Comfort = Air movement + humidity + temperature. Where Air movement should be slow (approximately 0.1 m/s), humidity is ideally 50% and temperature around 21 C °
So a major difference between the US7 and other AC units, apart from much greater efficiency, is the higher level of comfort (and fresher air) it creates in your home.
