Of all the options for off the shelf electric heating the oil filled radiator is probably best in terms of providing a more stable form of heat due to the slower way it heats up and cools down. With a fan or simple panel heater I find the temperature varies quite noticably as the thermostat switches them off and on. With the fan heater you've also got the added nuisance of the noise.
i've found an oil filled radiator for £24.99 it's 600 watt this means nothing to me will it be expensive to run?