"A flame produces far less light than electricity for the reader, but so much more pleasure for the diner." Meathead
I am going to be politically correct here, which is to say I am going to be polite to my friends who love their electric grills. I am not going to insult them by saying they have made the wrong choice. But I am going to try to prevent those of you who are shopping --I am searching for words here -- from making a horrible mistake.
Electric grills use a hot coil for heat. Often made from an alloy of nickel and chromium called nichrome, when a current is passed through it the nichrome resist the flow, gets hot, and glows. Although George Foreman, Cuisinart, Grundig, Coleman, Char-Broil, and even Weber call their electric devices "grills", there is no combustion, flame, or smoke, so I consider them to be large panini presses, or, at best, low temperature griddles.
Some have a griddle-like surface with ridges, and the theory is that drippings fall into the valleys, vaporize, and add flavor to the food, while the ridges produce dark brown grill marks. In practice, not so much. An inexpensive hardware store gas or charcoal cooker, well chosen, can cook circles around electric grills. They are really glorified electric frying pans. And remember, you need an outlet to make them work, so if you go to the beach or on a hike, you'll need a loooonnnnnggg extension cord. Read this article to calculate the size and capacity of the cord you will need.
If I look hard, I suppose I can find some redeeming features. Before you buy be sure to read my article: How to Buy a Grill for tips on thinks to consider when buying any grill.
Easy start. Throw the switch and electric grills are up to temperature in five minutes or so.
Temperature control. Just turn the dial. Alas, they rarely get above 400°F, so don't expect to do steakhouse steaks with a rich dark sear. And electrics with actual thermostats with temperature settings cost more.
Timer. Some have timers. Handy if you don't have a kitchen timer.
Price. Most are well under $200
Size. They are small so they fit on tiny balconies and porches. Now if you live in an apartment or condo and that's all they'll let you have, then so be it. But I see no advantage in an electric grill on the balcony when you can get the same results with a George Foreman grill on the counter -- other than it saves space in the kitchen. Alas, most are under 200 square inches, barely enough for 10 burgers. Most will do four burgers max. You will not be able to host the block party with an electric.
Non-stick. Some have non-stick griddle surfaces, smooth on one side, ridged on the other. This is a nice feature, not because the ridges improve flavor, but because they are easy to clean and the griddle surface usually comes off and goes in the dishwasher. This is cool because the valleys between the ridges are often hard to reach with a sponge.