Thing to remember is that max wattage you are going to get out of any 110 volt space heater is 1500 watts which gives you around 5200 btu's. Don't overpay because something looks fancy. We have a lake cabin that we heat in the winter with 3 space heaters we got from Walmart. Was just down there last weekend and the low at night was around 30 and they kept the cabin warm.
Walmart.com: Lasko Remote Control Ceramic 1500-Watt Tower Heater with Digital Display: Heating, Cooling, & Air Quality $45.00
They are not unsightly either.