Tom wrote:
They do work. I have one and the air coming out is very cold. The only
problem with them is that they suck air in from outside to replace the air
the blow out the vent through the window. Very inefficient.


The air coming in, is the same air going out after it has removed the heat
from the coils. Room air is not removed, nor is outside air introduced to
the room. I do see some inefficiency because of the fact there is some
restriction to air flow while doing this. In a window unit, the heat is
immediately dumped to the outside and doesn't have to be fan forced up and
out a tube.


Not true. They blow air out two places.
1. Evaporator air: Out the front vent (cold air).
2. Condensor air: Out the hose that goes out the window. (hot air)

Air for both #1 and #2 come from the air in the room. But if #2 is
blowing air OUT of the room that means that:
a. The room will eventually be sucked dry of air or
b. Air is coming into the room from somewhere else.

Unless a magician is creating air in the room then it has to be drawn in
from some other room, cracks in the walls or ceiling or somewhere else.