In many ways the Hot is a typical Dyson product: smart, innovative and arguably stylish, but unlike most Dyson products it fails to excel at its primary purpose. The Hot is simply not powerful enough to warm anything but the smallest of rooms and to do that you'll need it set to maximum at which point it becomes distractingly loud. As a desk fan the Hot works well keeping you cool in summer and warm in winter all the while incorporating a bladeless design and clever automatic shut-off should it be knocked over. As such it actually makes more sense than the cooling-only Dyson Air Multiplier fans, saving you the need to buy multiple devices. This would be enough were the Hot priced sensibly, but at circa £250 it's a signiciant chunk more than the Air Multiplier and nearly ten times the price of a conventional fan heater. All told, we think you'd be better off turning up the thermostat a bit.