We purchased one each for 3 rooms downstairs and in a word they work brilliantly. Upstairs has GDH so it was hideous going downstairs from the warmth upstairs. The largest room is a converted double garage and was so cold it was almost unusable, we were worried that the largest (2000 watt) model wouldn't do more than take the chill off, but the convection and radiant heat is great and this room is as comfortable as the rest of the house running that room at 20 degrees on the heaters thermostat, we had it running warmer but was it was too hot! The other rooms are smaller so they are toasty. We haven't had a bill yet but being able to run them at lower temps means they are running more efficiently so we are quietly confident that this will translate to being cheaper than other heaters we were considering. Couldn't recommend them more highly.