Kenmore 6,000 BTU Single Room Air Conditioner —
We installed this air conditioner in our family room, a 12 x 15 add-on to our house that a previous owner built with sub-standard insulation and poorly designed ductwork. As a result of its construction, cool air from the central A/C either doesn't make it to this room, or just gets overwhelmed by heat leaching in through the walls.
In the past we've jacked up our thermostat (turned the setting down) in order to be comfortable in this room. That's costly, and obviously amplifies our carbon footprint.
This summer we installed this unit in a window in the family room, and we were very comfortable all summer long. With the main A/C turned down (thermostat setting turned to a higher temperature) our electric bills have been quite acceptable.
The unit itself makes some sound. I haven't been up-close-and-personal with other operating window A/C's for a very long time, so I'm not sure how to compare the sound it makes with others. But I think it's sound level is acceptable, and certainly a good trade-off for the comfort. We watch TV a lot in that room, and the A/C did not interfere.
A minor plus was that I was able to program my universal remote control to operate the A/C, so we filed the supplied remote in a drawer and don't have to fumble with it.
Installation was not as easy as I hoped, but that's entirely because of the design of my vinyl window. I don't know how similar my window is to others out there, but its contours did not match any of the installation directions, so I had to improvise in order to provide a secure platform on which to rest the outside portion of the A/C.
I don't know if all purchasers of window A/C's do this, but I arranged with an electrician to install a dedicated, grounded, outlet for the machine, per the instructions. That obviously increased my installation costs, but it was worth it, since I didn't want to plug the A/C in the same circuit with my TV, DVD, and computer.
We also bought a 5000 BTU Sears A/C for our bedroom (and had a dedicated circuit installed up there too). That room is upstairs, and the central A/C seems a little bit shy about sending cool air up there too (plus a lot of heat radiates down from the attic on hotter days). We run that window A/C at night-time only, in the summer, and turn the central A/C setting way high overnight, with a timer.
The investment in these two Sears window A/C's has reduced our electrical bill and increased our comfort, so we are happy campers!