"This is an evaporative cooler, not an air conditioner; its effectiveness is entirely geography-dependent."
The promise of a 'Windowless Portable Air Conditioner' translates to an evaporative cooler. Unlike a real AC which expels heat and moisture outside, this device adds moisture to the air inside your room to create a cooling sensation, a process that fails in humid environments.
This is for someone in an arid, low-humidity climate who wants a modest cooling effect with minimal electricity use. It is also for a user who specifically needs to add humidity to a dry room while circulating air.
Anyone living in a region with moderate or high summer humidity should not buy this. If you need to significantly lower a room's temperature or remove humidity, you require a real portable AC with an exhaust hose.