X2
The Big Buddy heater is great (but the size has limits). Mine easily heats a 20 x 18 foot room, then maintain the heat between the two settings (just press down on the knob and turn it half way to the next setting. I also take the grate off and hook it through the handle and place a heat powered fan on the grate. WITH THE GRATE OFF MAKE SURE NOT TO PLACE ON A SURFACE THAT CAN MELT OR IGNIGHT (put foil on the floor or elevate on a table and place at the edge of the table). By removing the grate, you are moving the heat shield.
See the picture.
In the first house my wife and I purchased, we used a vent-free gas log set as our main source of heat (heated 1500 square feet. We took out the wood stove because it would get up to 80 degrees in the living room and it created a mess with the wood. No issues with air quality and the humidity level only increase 1percent after one week (compared with electric heat after one week). My father used a vent-free gas log set as his main source of heat and that is what sold me on getting one for my home.