The main advantages with gas heating is it is more economical than oil and it is a clean fuel. Oil is very expensive and is not that widely used only in rural areas where there is no gas supply fitted to the properties so oil has to be used for this purpose.
The cleaner burning properties of gas is a green benefit. Oil fired furnaces while used a lot up north and on the east coast, are harder to maintain, and oil is getting very expensive. The oil fired furnace usually requires a boiler, and a radiator system in every room in the house. Gas systems use a conventional air handler.
Gas heaters are much cleaner as it don't cause bad smell and they provide much more heat than oil heaters .
Most Gas heaters are supplemented with a sensitizers that turn it off once it falls back so it's safer than the oil eaters which are one of the leading causes of houses burning .