I just received this pressure washer and assembled it right away - a 10-15 minute job. I proceeded to test it on some old and filthy concrete and was surprised by how powerful it is. In addition, it's significantly quieter than a gas-powered version that had been used several days ago to do some cleaning around the house by a hired hand. Never having used one of these pressure washers before, I quickly became addicted to how readily it made light work of removing grime. In fact, using the green or red nozzle placed very close to the concrete (1 or 2 inches) will actually remove a skim coat from the concrete - I could tell this because it produced the same smell of grinding concrete as when I've ground concrete using an angle grinder. So be careful if that's not your intention - keep sufficient distance between nozzle and the work surface. The motor's rated at 14 A and I've had no problem running the pressure washer continuously for about 30 mins from a 15 A GFCI receptacle. The high-pressure hose is somewhat stiff and I wonder whether a more flexible hose rated for such a high pressure is available. But so far, I can recommend this very highly!