When it works, it works fine if I'm sitting in front of it. It maintains the temperature on hot days, but most of my space was still not cool even though I had the fan set to highest and temperature set to lowest. 
My biggest complaint is that I must have gotten a defective unit or something because this thing randomly will change temperatures and fan speed. The remote only seems to be responsive half of the time even though the batteries are new the display lights up like it's working. Also on energy saver mode this thing seems to never turn off even though it goes four or five degrees beneath the temperature I set it to. 
I haven't had this thing a month in my energy bill is already higher than the estimated yearly energy star cost because the thing would never turn off. It's still much lower than what another AC without the dual inverter would have been though.
The high setting is quieter than my $10 small tabletop fan on the fan's lowest setting.