Some equipment manufacturers divert the refrigerant gas to and air-to-water heat exchanger then move that water to another water to air heat exchanger to condition the air.  Although it may be easier to design a system this way, it is much less efficient.  The compressor needs to work harder since it is more difficult to transfer the energy.  There are also additional pumps, valves, control, and heat exchangers to fail.  The SelectAire Plus is designed to directly exchange the energy from the refrigerant heat exchangers to the air.  This reduces complexity and increases energy efficiency.