This is one of those questions where the best answer is, it depends! It depends on your wants and needs. Both fuels come in lots of traditional and linear sizes. Both have several media options for a unique and customized look. But, are you looking for much heat? If the answer is yes, go with gas.
If space limitations and/or venting issues make the project difficult, an electric fireplace would be a great choice. If a little supplemental heat in the room is all you’re after, go electric. Maybe you would like to enjoy the flames and lighting effects year-round. If so, operating an electric without the heat option will work out well.
If you want to use some zone heating techniques and stay comfortable in those two or three rooms of the house where you spend most of your time, a gas fireplace would be a solid option.
Heat, price and installation details are the three main variables to consider when contemplating an electric fireplace vs. a gas unit.