Should i go with a Gas or Oil Boiler???

I currently have a old oil furnance from probably the 1930, you know old huge cover in asbestose... I just recently put in a eletcric hot water on demand system. I wqas wondering should I go with a Gas or stick with oil for a new boiler. I am planning on sticking with the steam becasue i dont want to rip out all the radiators and switch over to base board it seems like a lot of work. Any idea?