No problems so far. This AC does what it is designed to do: it pumps cool air into a warm room. Nice range of fan speed and cooling settings. The unit is a little noisy when the compressor is running, but that's par for a small unit. A big upgrade would be a clock allowing a programmable turn-on time so a room could be cooling for a few hours before being occupied. The available timer function requires entering the number of hours before you want it to turn on, and requires good math skills.