I've only had the ac operate once.  After letting it acclimate for 24 hours I set her up (very easy) and she worked well.  I had to shut it down for a conference call.  The unit does make some noise but I can deal with that. The unit is HEAVY. I set it on a stairway landing, three steps up, and close to a window for venting and pulled a muscle in my back.  BE WARNED!  Well packaged and works well.