I bought a house with an old oil furnace. When budget permitted, I replaced it with a gas furnace. I didn’t let the type of furnace sway my decision to buy, but (all other things being equal) I would prefer the gas furnace to oil.
A question, though - When I converted, I had to get the gas company to okay the additional load created by the furnace. According to what they told me, they model demands based on their existing piping and may not be able to support additional demand.
This is getting beyond the OP, but here are some things to consider between the two:
Furnaces (oil or gas) should have at least annual maintenance. Oil tends to be more messy and finicky; however, any good oil company should have technicians on-call around the clock. (My brother’s wife’s family owns an oil company and he delivers oil and fixes furnaces. He is always on call during the holidays.) Furthermore, they’ll usually schedule their maintenance with you during the summer to service the burners. Some gas companies have separated themselves from maintenance, and you’ll need to contract with an outside firm to provide this.
Oil tanks take up valuable space in your basement if you have one, or elsewhere if you don’t. I don’t know if it is still legal where you are to bury an oil tank below ground, but don’t do it. Just don’t. Gas just requires a meter and a pipe.
You can get an occasional whiff of burning oil from your furnace. Not so with gas.
Gas can blow your house to matchsticks. Maybe it’s my imagination, but whenever you hear of this you also hear that the gas company was doing some work in the neighborhood not long before. The gas company has been working on my street over the last month to replace services to homes. So yeah, I’m a bit nervous.
The new gas furnaces (I have one) are energy efficient, involving preheating air, purge cycles, what have you. It’s all controlled by a circuit board. If the circuit board fails (like what happened to me), fate dictates that it happens on the coldest day of the year, and you’ll be staying home waiting for a tech to tell you that they don’t have it in stock and can you find a place to stay? because tonight’s even going to be colder, maybe even breaking a record.
Gas is on demand; you pay for what you used. Oil is in reserve; you pay in advance for what you might use.
In short, gas is cleaner but there is that concern over pesky explosions. Oil is more awkward, but I think that the service is more reliable.