I used a catalytic propane heater in a pop up last year for the first time. It only seemed to do much if I put it between my feet and caught the radiant heat coming off it. It sure didn't warm things up enough to take off your coat or anything. None of those blinds are insulated or windproof enough to get really warm. When it gets really cold here I guess I will try it again this year but I'm not sure it is worth the hassle or expense.