"A noisy, power-hungry spot cooler whose main sin isn't performance, but misleading specs."
The 12,000 BTU rating is the less stringent ASHRAE standard. Expect it to cool roughly 300-350 sq. ft., drawing around 1250 watts when the compressor runs, which will be often.
This is for someone needing to survive a heatwave in a small bedroom or office, who prioritizes low upfront cost over all else. If you are a renter and cannot install a window unit, this provides brute-force cooling.
Anyone sensitive to noise, concerned about high electricity bills, or trying to cool a room larger than 350 sq. ft. should pass. A dual-hose portable or a proper window AC is a much better long-term investment.