Oil Filled Radiator Heaters do work great as supplemental heat and I have one in my bedroom.
My bedroom gets the least heat from the furnace and the radiator filled electric heater works great for warming the room up.
Oil filled radiator heaters do work to warm up a small room.
However the oil filled radiator heaters are not meant to be a sole source of heat but instead they are meant to work along with your furnace or other heat source.
Trying to heat an entire house with electric oil filled radiator heaters will raise your electric bill up and you'll still be slightly cold.
But when the oil filled radiator heater is used as a supplemental heat source they work just fine.
Oil filled radiator heaters cost the same amount of money to use and run as regular electric heater.
The oil filled radiator heater uses the same amount of electricity per hour than a fan heater or other electric heater but the oil filled radiator heater produces steady heat and is quiet as well.
Oil Filled Radiator Heaters are not cheaper to run than other electric heaters.
The oil filled radiator heaters use the same amount of electricity to operate like the electric fan space heaters do.
An oil filled electric radiator heater uses a heating element that is submerged in oil and that heating element draws 1500 watts of electricity when on high.
That heating element heats the oil up to the hot enough temperature and then shuts off until it needs to heat the oil up again.
So in a way the electric oil filled heater may use slightly less electricity because it's not on all the time unless it's really cold.
But the wattage of the oil filled radiator heater is the same.
Oil Filled Radiator Heaters are safer than electric fan heaters but they can still catch things on fire and you must keep things away from them as well.