We use this in our bedroom which is 20x12 and it cools it down very well.  We keep our bedroom door open and a fan blowing out into our open concept very large kitchen and living room.  While it doesn’t get it cold, it certainly does cool the space well enough to keep us cool while just sitting and watching TV.  We get the afternoon sun in the bedroom and living room so it can get quite hot in here.  We are definitely happy.  It’s loud, but for a portable AC unit I’ve definitely heard worse.